Repairing the ?black foam coming out of vent? issue

Did another repair of the �black foam coming from vents� repair on a clients car today ... this also causes loss of the ability to heat the interior too, since the foam loss allows cold air to come directly in through all the holes in the vent flap as shown. I do this repair a lot as all 996, 986, 997 and 987 Porsche�s will suffer from this issue. here are some photos of how to do this repair ... hope it helps some facing this issue. Check out this and other projects at my Instagram page #joeslastchancegarage Removing the wiper mechanism ... as you can see, I�ve already removed the wiper arm, the cowl panel and the battery to gain access Removing the strut brace to get access to the heater core area ... note I�ve already removed the main strut brace bars in this photo Remove this rubberized panel by gently pulling up at the edges to separate from the sealant ... don�t rip this panel so take your time Clamp off and remove the two coolant hoses ... use some paper towels to catch a little coolant that comes out ... should not be very much if you clamp the hoses as shown Remove the heater core This is the only �mod� ... carefully cut off the top of the flap pivot housing ... just about 4 mm is all you need to cut off Here it is with the top 3-4 mm cut off and you can see the flap pivot This is the flap pivot removed ... just use a small pick to carefully pull it up and out Removing the lower flap pivot ... it�s only help on by a single screw and the flap motor pivot and then pull down. Reach in and remove the flap Flap coming out ... note all the foam has fallen off and most came out through the vents ... the �black foam� apocalypse every 996, 986, 997 and 987 owner will experience at some point Flap fully removed and note all foam gone ... these holes allow cold air to come directly in, preventing any heat inside the cabin. Remaining foam removed from the heater core box Foam adhesive also removed from heater box Replacing lost foam on the flap Replacing the lost foam Me replacing the lost foam This is what it looks like with the flap repaired ... I put foam on both sides as the factory did, but this foam should last much longer Vacuum out any remaining foam in the heater box ... there could be quite a bit Reinserting the flap ... it is critical to ensure you put it back in the exact orientation that it was originally in ... it is easy to put it in backwards and if you do that, it will not function correctly Put the flap pivot cap back on once the pivots are reinstalled ... I use black �dum-dum� to hold it on ... works great and avoids problems using glue or epoxy fouling the pivot. Now just reverse the steps above to reinstall everything.

Thank you!

Outstanding I will tackle mine now.!!!!!!!

Great pics. How exactly are you putting that cap back on in the last pic? Does that stuff go over top or what?

It’s a semi-sticky and stretchable material kinda like play dough (but rubberized and meant for cars) so it forms a moldable cap that I use to secure the cut-off plastic pivot cap ... it’s flexible and sticky enough to keep everything together. It’s the same stuff 944’s have used from the factory to seal the tail lights. ... I get it in rolls and then just cut off a bit, form a cap as shown, then put it on and form it around the housing to hold it together. Very easy and cheap but effective and long-lasting.

Thanks for posting this, much easier to follow than previous versions I've looked at. After many years, most of my foam seems to have worked it's way out of the vents so I only get the occasional piece now. One question though... you mention the car won't heat up well without the foam ? I live in MN and drive mine daily and even at below zero temps have no issues with heating up inside the cabin, so I'm not sure if this is necessary ?

My experience is that the loss of foam (as in this example) greatly reduces the heat capability in the cabin and after the fix, it is much, much better. Can�t say for sure in your particular case, but I suspect you�ll get better heating after the fix.

Quotes source post: 16441612

Interesting, I live in the Chicago area and don't really drive much below freezing because of my heat issue. It takes a while to heat up and I usually have to keep it on HI at all times to keep up with extreme cold. Luckily I don't have to drive it in extremely cold weather. I'll probably tackle this at some point and this is the best write up and pics I've seen on this issue so far.

R324U ... this fix will definitely help with your heating issue ... all of my clients are amazed at how well the heater works (gets really hot inside on HI) after I do this repair.

Quotes source post: 16441612

My foam blew out over 10 years ago. Shop vac, high fan speed and cleaned it up. It stopped blowing out foam, and I have never noticed any difference in heating and cooling. I know that this "fix" is for the fresh air blend door, but again, I get hot air, nice and toasty, and nice cold air in the summer. You might say, well of course, you live in Florida. But we do get some 20 degree days and it has always worked very well getting warm in the cabin. I would undertake this project if there was a problem, but I don't have a problem with the way it works now.

Great for you ... Glad to help others with this info.

Is there any particular reason why you don't use aluminum tape (meant for ductwork) instead of foam? Are you suggesting this is an easier, more efficient, fix/repair than going in through the center dash? Thank you for the post!

I think if you turn off the A/C compressor (snowflake button), you can "survive" even with a de-foamed vent door. The A/C runs even when on heat, especially when in defrost mode,( to keep fog off the windshield), unless you manually turn it off. AMCPILOT ,very nice write -up and pictures, I wish I had a write-up/pictures like that for my UAOS install procedure !!

You can use whatever material you like ... I have found this foam to be easy to install, inexpensive, and long lasting. I've found through experience and actually doing this dozens of times that this is a very effective solution. To go through the center dash, in my opinion and experience, you have to remove the entire dash, A-pillars, center console and the steering wheel just to get access tot he HVAC housing. I've seen some really butchered attempts at going through the center without removing the dash, but whoever did it and posted about it really destroyed a big part of the car. It was really an amateurish and destructive way they went about it ... not recommended. I can do my method in about an hour from start to finish. I have done it once by removing the entire dash and the HVAC box but it was prohibitively time consuming, costly, and complex. My client was finicky and wanted it done this way, but then complained about how much it cost and the time it took. I don't recommend it, but people can choose to this however they like. I'm just trying to help others .. and this is just one way to approach the problem. Not sure if I can really add any more to what I've tried to convey.

thank you! great writeup. I have this issue on my new to me 2003. I think most of the foam is out but super annoying anyway. i hate the little particles on my dash etc. I rigged up a tube to my shop vac yesterday and tried to suck a bunch out... one question, after reassembly do you need to bleed the coolant system?

The way I do it by pinching the hoses off and then carefully pull the heater core straight up while using my fingers to block off the inlet and outlet, I lose about 2 tablespoons of coolant ... not need to bleed out the coolant because of this ... at least in my experience. I run the heater at high for a few minutes after all is back together just to be sure. I'm sure there will be someone who will say that you have to bleed the coolant system ... if that's how they have actually performed this repair, then great for them. I haven't had the need to do so.

Quotes source post: 16442086

Going through the center of the dash I believe is for the door that directs the air to the specific vents, the blend door above is for hot/cold mix.

Quotes source post: 16442272

This. Through the dash you get access to the second blend door (there are 2).

Alright so between this thread and the last one I decided to say screw and attempt this fix. I have some things on order but I went ahead and began disassembly, so far it is way easier than I thought and has taken me about an hour. I am up to the point I need to cut the notch and take the arm off under the dash and then pull out the flap. This is the first project I've personally attempted with my 911 besides wheel spacers and it really is not bad so far. At this point, I would rate it a 3/10 in terms of difficulty. The only tricky part is some of the maneuvering you have to do. Question, for the foam piece that covers the actual heat radiator, do you put a new seal down? A lot of that stuff got kind of mangled while I was trying to get it off. It's like a sticky putty that has a lot of stretch to it.

Is there enough space/access to apply new foam without pulling the flap out? An arthroscopic surgery equivalent?

Quotes source post: 16443868

Maybe if you have the world's tiniest hands. I can stick my hand down in there and feel the flap but I have zero room to maneuver. By the time you get to this point all you have left is the cap and bolt under the dash. The cap was the worst part so far, its hard to get in there and cut it.

What do you generally charge to do it? Just curious, your not far in SA.

I guess on the positive side I don't really have to clean it off.

This looks like a very practical project and because it addresses the outside air supply. The dehumidification must work better when in re circulation mode. I have noticed that the windows do not clear as fast anymore since the foam started blowing out at me.. . On a 996.1 how do you access the bottom pivot screw? Any pictures? What type of foam do you sue? Source?

What do shops charge for this repair? Mike

Quotes source post: 16443953

Can't speak for OP but I have a 996.1, the bottom pivot screw would be where your left foot sits if you are a passenger in your car. There is a piece of thick foam under your dash and you can peel it back enough to get the little bolt out. The area is easy to spot because its the only piece down there that is pink. It is awkward to get in there but the arm will come off once you undo the bolt. After the bolt and arm are out you can use a pick to pull out the plastic cylinder connected to the flap itself. I just ordered some generic HVAC foam adhesive and I think I am going to wrap it in some HVAC foil as well.

I charge $75 for the entire job including vacuuming out/cleaning out the vents and defrosters to get as much of the black foam material out that seems to get everywhere.

^^^^ That seems very very reasonable! Mike

Quotes source post: 16444120

That is a great price considering what labor is here in the NE. I could see how you could blow through this real quick once you've done it a few times. Honestly, the only bad part is getting the cap off and getting under the dash is just a bit awkward. That being said I am a bit nervous to put it back together, at least getting the flap back in. How do you know if it's seated properly?

Once the pivots are put back in and before you attach the lower lever arm off the electric motor (passenger footwell), you should be able to move the flap back and forth freely. If it does this, it�s seated correctly

Quotes source post: 16443819

Ok, so once you fix the flap all you have to do is clean the area all around where the heater core came out of... GEEEEEEZZZZZZZ it looks like it's never been cleaned for the life of the car

Feel like making a road trip to Florida?-lol

Quotes source post: 16444775

Ha! Uhhhhhhh... NO! Just think of how good you'll feel knowing everything is spic and span under the plastics...

Quotes source post: 16442086

When I fixed mine, I was able to apply HVAC tape to the flapper without removing it from the car. My foam was 100% GONE. Even though I used aluminum tape, my heater began working fantastic right away. If you have some foam left, you are better off removing the flapper, cleaning it and using foam .. only because it is more 'factory' that way.

I am going to clean it up and restore the plastic pieces while they are out.

Quotes source post: 16444906

I used aluminum HVAC tape also. Unfortunately I didn't notice as much an improvement in heating as I thought I would...

Just finished up and I now have scolding hot heat again. Reassembly was much harder for me personally. First things first I got the rad back in the box and bolted down and put the rubber cover on before I second-guessed myself on the position of the flap. Had to disassemble and I am glad I did because I had the flap in backward, make sure the point where the smaller and longer part of the flap meets face towards the front of the car. After I got it all bolted up I took it for a drive to get it up to temp and of course my world came crashing down when I had no heat. I got home and had my wife play with the buttons and realized I did not have the arm under the dash oriented the correct way. I popped the arm off and turned the flap by hand and immediately had heat so I knew it was the arm. It is hard to orient yourself down there but it was actually easier with the car on and heat on full blast because then you can pop the arm back on and you know its in the right position. I have lots of foam and foil left if anyone wants to tackle this just pay shipping and I can send it out provided its less than the cost you could get it. Thanks to the OP for the guide and for answering questions on the fix.

Quotes source post: 16444922

Yeah! It'll be soooooo much better!

This is an excellent thread. Thank you so much for posting AMCPILOT. I've book marked all the posts I could find on fixing the "blowing foam syndrome" but yours has the best photos and documentation I've seen. Its been on my to-do list for a few months now. One question, since you've done this a number of times now and you've gotten past the learning curve, how long does it take you to do this repair?

Wonder why Porsche used foam to cover the little holes instead of just making it a solid plastic piece with a foam surround? I need to do this eventually as mine has been blowing chunks for years with no signs of stopping.

A great write-up and good timing as my upper vents are now only blowing cold air. And foam. AMCPILOT: is there a way to remove the vents to vacuum out the chunks of foam, or can you get to them from the heater core area?

Thank you AMCPILOT. Just got back from testing mine, 25F outside and toasty warm inside. Definitely couldn't have done it without removing the flap. Could have gotten the small side, but not the whole thing. Took advantage of the opportunity to clean the panels and under the covers so dporto wouldn't pick on me . As a bonus, found that the PO didn't bother with a battery hold down, so I added one of those. One suggestion for those who are doing this -- if you have power seats, move the passenger seat back before taking out the battery! Looks like black nacho chips hiding down there.

I vacuum as much as possible from the heater core area, then use a vacuum and long pick to pull out any in the vents (don’t have to disassemble anything), and also vacuum the defrost vents.

Quotes source post: 16450353

Porsche isn't the only one, VW, Mercedes, BMW all do it. Supposedly it allows a "little" bit of air to flow, thus the "blending", and it's supposed to be a little quieter.

I'm long time lurker, infrequent poster. However, I completed this flap repair a couple of months ago, and despite finding helpful threads here and on other forums, I could not find any pictures of what needs done on the bottom interior. Lots of details of the top, like AMCPILOTs great pictures and instructions, but I was really lost trying to figure out what to do on the bottom. So, here are my pictures. I hope this helps someone. EDIT: There are a few other pictures, including one of the bottom area here: https://www.renntech.org/topic/47275...-out-of-vents/ EDIT: I have a 2004 C4S. Some people have posted that the clips could not be removed on their C4S or otherwise wide-body car. I don't know about theirs, but mine looked as posted here, and by AMCPILOT, and I finally got everything fixed and back together just fine. Under the dash. Remove the small screw on the end of the lever arm. Screw removed and arm moved aside. From my boroscope camera (it's that tight down there). I used some long pliers to grab the plastic clip. It was really hard to pull out, since it's clipped onto the flap above. I also used a small screw driver to pry gently. This was the hardest part, and I almost gave up, thinking that I would break something. Success! (bottom of flap is just visible in the hole) Here it is. When putting the flap back, I had to use a small screwdriver to get the flap aligned perfectly so that it clips back into the plastic clip. Once installed, twisting the clip down here should perfectly twist the flap. If there is any slop in the flap rotation, then the clip didn't clip back onto the flap, and is just pushing it around.

My arm came off which made it a lot harder since I didn’t remember which way it went. My clip came right out which was nice because it’s awkward working under there.

Did mine today. Five more tips take the battery out. It gives more room. like I think I saw in one thread, Mark the wiper location on the glass with tape. the bottom plug is easy to remove if you put the screw in part way and pull down on the screw to pull the plug out. make sure you run the foam around the vertical outside corners It not thick enough to rub on the plastic at the bent point air gets by. when I took the cap off the bottom the pink arm was in one position. When I went to reassemble, it had moved. I think the thermostat required it to be in a different position so it had moved. I had to play with the temperature button to get it to move to its original position. took me about 4 to 5 hours. I am very slow.

Has anyone reviewed this thread? There seems to be another blend door with oval holes that is not accessible from the heater core. http://986forum.com/forums/performan...-debris-2.html Any idea what this one does?

I believe it directs air to the different vents (footwells, defroster, dash vents) inside the car.

Thanks for the writeup. This is very clear instructions. I wish you were close to me to do it. ha

Quotes source post: 16456788

Yes, this is what I and others have said on this thread. There are 2 blend doors. Second one, as R234U said, directs air to the different ducts. You cannot get to it from the bonnet.

About to do this, still researching the best solution. Looking at some of the questions posed earlier, why did Porsche, BMW, etc. use open-cell foam and not a solid plastic or aluminum door? I am starting to think there is some need to let some fresh air into the blend and therefore use open-cell foam. I’ve seen DIYs from other forums where people used filters from room a/c units, etc. vs. foam or aluminum tape.

Thanks for the great write up. I did BOTH vent repairs last weekend and took less then 4 hours to do both. 2+ hours to do the "heater core one" (has the round holes) and 1+ hour to do the "behind radio one" (has the oval holes). After i took apart the one in the frunk per AMCPILOTs great write up my flap still had a ton of foam tape on it. It just didn't make sense that i had so much foam coming out of the vents over the years. So in the middle of the repair i did some more research and found out about the second flap. When i got access to the second flap that one barely had any foam left on it. So that's where the most of my foam came from. With the "heater core one" mostly in tack i would have foam coming out for long time. Because of the foam problem i rarely used my vents....and when i had to defrost windshield it annoyed the heck out of me having the foam bits get everywhere....all over the dash and i'm sure fine foam dust all over me!! It's soooooo nice now to use the vents without the stupid foam dust coming out of them. I attached the link that i found that shows the second flap and how to get at it. http://986forum.com/forums/performan...-debris-2.html

Just wanted to say thanks for a great, detailed write-up. I think I know why I have been getting the foam shower. I would not have attempted this fix without this - by far the most difficult part was cutting the cap off. Speaking of the pivot cap, what is everyone using to re-attach? I was thinking about using some clear silicone caulk.

I had a plastic cap that was the right size to slide over the original. Slid that over the top of the cut-off piece and epoxied the cap so I didn't gum anything up. Used a coping saw with the blade turned around to cut the cap.

A couple other tips for this: -clamp BOTH heater hoses before you begin to loosen them. Doing one at a time will lead to losing more coolant than you want to.... (ask me how I know) -you can secure the cut-off cap with duct tape. Yes, most of you are about to scream right now, but compare this to the putty originally suggested. I used black duct tape that is very secure and you can�t even see it because of the color. Otherwise, a good repair procedure that didn�t take too long.

First of all I would like to thank Joe Tegtmeyer ( AMCPilot) for his very helpful DIY. I fixed my flap today but was surprised to see that its design was different. My 996 C2 is has been built in 1998 which explains perhaps the difference? Every thing was the same until I removed the heater core. The flap is a smaller one covering only the passenger side of the black box.. I have been able to remove the remaining foam and to replace it without removing the flap. I just release the single screw inside the car in order to move freely the flap. After removing the remaining foam and vacuum Flap Open: Foam installed on both sides, covering the edge Flap closed

Quotes source post: 16936113

Check again. Your flap is just like mine. If you follow the procedure originally suggested, you will see that your flap is L shaped as well. The rest of the flap is to the left in your photos. The longer part is hidden behind the rest of the duct. You have replaced the foam on the short section of the flap, but the longer section of the L is still back there.

Quotes source post: 16938048

Thank you for your advice. I was afraid of that.after reviewing some pictures of the flap. .. I will have to take the flap off to complete the job.

Quotes source post: 16938048

You were perfectly right. I redid the job today but took off the flap in order to fix the large hidden part. Took only 1 hour and 1/2 today... I'm becoming an expert of the heating core flap I didn't delete my initial post as it may help someone else to repeat my mistake.

I documented also some steps in this thread.....a few tips on post #15..... I decided to fix the foam problem while replacing a leaky heater core: https://rennlist.com/forums/996-foru...the-vents.html

Quotes source post: 16929744

I also used black Gorilla duct tape.

Quotes source post: 16942710

Didn't even think about black tape, I used the putty. I have no regrets doing the job the way I did it, it was easy all things considering.

Adding more to this thread. First off, thanks to AMCPILOT for posting this content, super helpful. I recently purchased a 997 and the very first thing I noticed was foam shooting out the vents and what I can only describe as sound like pennies jostling around in dashboard. I took the car to a shop and was quoted $7k to fix the foam issue. Eff that. I found this thread and was hopeful this was my issue, and got to work. Sure enough: Excellent... after a bit of dremel work, here I was: I was feeling pretty good until I read this entire thread and realized there is another flap that also might have issues that is not accessible without taking the entire dash out, or cutting up some the duct work from where the PCM lives, I thought maybe I could see if through the heater core opening and sure enough: It was almost bare. Shoot, so I found some videos and FAQS on how to cut the duct work to get to it, and took a look if that was an option on my 08 turbo cab, negative. I realized I could get my hands on that second flap, it wasn't comfortable, but I could do it, so I hooked up some jumper cables and moved the flap into it's three positions, great, I can totally get my hands on all parts of this flap. You can see it moved: Then I cut out some new new foam went in by feel only. I was able to totally re-foam this entire flap through the heater core cavity, I had to move the flap into the 3 positions so I could get it totally covered, it took a couple strips/passes per side, and it was a bit time consuming and slightly painful on the wrist, and I had to redo a couple of the attempts because I put it on crooked the first attempt, but all in all, it wasn't that bad. I was able to completely cover that flap all through that heater core opening without having to make any cuts, or remove anything other that the initial guide AMCPILOT provided. And the good news, no more penny sounds coming from the dash, no more foam, and now not only does the heat and cooling work much better, I can actually direct it as well. woot woot! $7k saved! Hopefully this is helpful for others looking to fix this issue

We did this repair for both flaps according this You Tube It was rather easy, and took about one hour. Local indy quoted ~ 600€ if done from outside.

Quotes source post: 16993247

That doesn't appear to be a viable option for the 997 turbo at least. You can't cut the ducting as you can see from the pics I posted

What does the other flap do? Direct air to the vents?

Quotes source post: 16993852

Yes. That's correct.

Quotes source post: 16993757

Thats right, I supposed that this is �996� thread

Quotes source post: 16441365

Did we ever figure out what this is exactly? I've been searching and even reached out to AMCPILOT directly. Unfortunately, his mailbox is full. thx!

Quotes source post: 16995759

This is what I used Amazon Amazon

Looks like exactly what I need to do - thanks guys - awesome info !

I have a2003 996 and have it all apart fixin the baffle next to heater core w/ new foam tap, and ready to put it all together, and can anyone tell me where and how to get to the second baffle?, I can�t see it from the opening at the hearer coil. Thanks.

Thats a take the radio and all that stuff out and cut the vent. You Tube

I just finished putting my 03–996 back together and it’s working great everything works as it should, but now my heat and AC are really working like I’ve never had. PO apparently got all 5he foam pieces he wanted, and traded it in, that’s 2hen I bought it 2 years ago. It needed a LOT of “fixin” , which I’ve done. So, in this operation you did on the video. What car are you doing this on?, is this what I need to do on my ‘03 996? to get to the second baffle? My neighbor is going to go nuts, as he just helped my do my car today. He’s not going to believe he’s going to help do more. I can probably do this one by myself, I’m only 80 years old and still doing things like this. Helps keep me “young at heart”.

I’m loving my car more and more, 5he longer I have it (2years now), and the more thinks I fix, the better it is. I’m al ost done, need to put in brighter console/instrument led lights, and maybe in the spring, upgrade the shocks, and I’m pretty much done. Just go and enjoy it and the maverick Porsche car club.

I did my flaps last evening using the video technique. Not a bad job at all. I found out why my heat/cooling was still working despite all the foam coming out the vents. All the pics and descriptions I’ve read show the foam off, leaving a bare metal flap, but on my ’03 there was a “skin” left behind, almost like plastic wrap, only sticky on the metal side. I had to peel all this remaining material off before putting my tape on. This was the worst part of the job. I used a wide, foam/foil backed tape, that covered in one piece and it slid in easy. Trying to clean up the residual foam was a PIA and I’m sure I’ll still get some out vents before it’s all done.

Can anyone recommend someone on Long Island, ny who does this repair?

Can you do this procedure on a later model 987 cayman?

Can this procedure (heater core) be done on a 987 Cayman? Thanks

Since I’m a new e to Porsche, and mine is an ‘03 Carrera cabriolet , I’ve only been working repairing items that I’ve found needing work on my 996. I would contact a local Indy, and ask about different models as I’m not versed in how other models are built. Mine is vastly better now and I’ve only done the two flaps , one from the inside pax side, and the other from under the funk lid, under the middle of the wind shield. I understand there’s also one a bit behind the center infotainment ( center upright) area, I need to take out, not much problem, and it’s straigh5 back behind there, w/ 2 panels that have holes in them, that will need to be redone. That’s the best I have on all this right now. Dave

Hey what kind of replacement foam are you guys using? I'd like to get something that lasts. M

I went to lowes and got some foam with one side sticky that you peal the tape off of, and about a 1/4� thick by about 1 1/2to 1 3/4� wide and taped both sides and I�ll see if i can post some photos here This is the diverter cleaned up ready for new foam tape Done Overlapped about a quarter inch and pressed both sticky sides together to help it not come apart The hole in middle is where diverter goes It�s a bit fiddley, but if you go slow you�ll get it done. I foune a thread on rennlist as to how to take it all apart and reassemble with pictures Another finished picture

Thanks. Was that insulating foam for windows/doors?

I used this insulation tape. Worked very well. https://www.homedepot.com/p/Armacell...8230/100539553

Quotes source post: 17207635

Perfect! Thanks M

Quotes source post: 17207447

Can you post the thread please. Ive been looking for it. I think I would rather do it this way. Seams like the access is good enough. Thanks

I also used foam insulation tape and took it a step further and wrapped it in aluminum foil tape.

Quotes source post: 17208954

I went over to Lowes and couldn�t find the exact tape i used and other plumbing and electrical stores were closing so nutz. I need more myself as i still need to take out my center infotainment area and do the baffel back ghere. I see lots of closed cell tapes, one sticky side on Amazon, so I�ll be looking for either 1/8� or 3/32� thick and somewhere in the 1 1/4� to 1 1/2� wide closed cell , one sticky side and just get it on Amazon. Pretty soon.

Great presentation, since I have fat fingers and half blind for close up work, does anyone have a recomendation of a shop in So.Cal (Orange County) that would be recommended for the repair? 2005 - 997.1. Cost is not really an issue within reason :-)

Quotes source post: 17209155

Duct tape, works for everything!

You seem to be the expert on this problem. I am having this problem with my 2007 Cayman. I have removed the heater core and then tried to remove the blend door, I can't find the clip to the bushing on the bottom of the blend door? so I can't remove the door to refoam it. I am at my wits end. Did Porsche change it on the 987 models? I find it hard to believe that I am the only person having this problem I can't see any posts on this problem on 987 Cayman? I hope you can enlighten me so I can put this car back together again. Thanks' Fred in Charleston SC

I have a 2004 996, but I documented removing the bottom end earlier in this thread. Is yours different than that? https://rennlist.com/forums/996-foru...l#post16454725

I completed this job yesterday and it was a pretty easy fix. Thank you for coming up with the method, @AMCPILOT ! I could tell the difference immediately and the car started to produce heat before coolant even came to operating temp. By then it was toasty. As many others, my foam was completely gone and left overs were so dry they turned to dust. Few takeaways after finishing....1) Be careful removing the heater core. The fins are super thin and it's quite easy to bend them. Lift up slowly. 2) Clean out all the water drains while doing the job. They clog over time. 3) I didn't have the time, but I'll be removing the battery tray to repaint it as it's forming some rust spots. 4) For plugging the 2 coolant hoses I used bar end plugs that I had laying around. These are used on road bikes after you wrap the bars and are used to plug the tape ends into the bars. Fitment was perfect and easier than clamping the hoses. I suppose a wine cork could work too

Thanks for the write up. I did this and changed the cowl at the same time. Took me 3hours. Definitely hotter although not night and day. M

Fellow San Antonio enthusiasts, I tried to reach AMC Pilot on Facebook...no response. Anyone know if he's still around? $75 seemed too good to be true...now thinking it was, ha! Thanks

Quotes source post: 17290084

Yes, he's still around. He's a very good friend of mine. Lives not too far from me. He's taking a little Hiatus from working on Porsches for a while. He bought a Tesla and he's been going to the Austin Tesla Factory and using his drone camera to take pictures of it everyday and videos. He posts them on Facebook.

This is most helpful. I talked with a tech that said the whole dash needed to be removed. Glad I didn�t go with his offer as this seems doable. I live in south Texas so it doesn�t get that cold (except for nuclear winter we just had -which it stayed in the garage anyway) for this to really matter. If I ever really want to tackle this, I know where to go. But I was wondering: What about blowing compressed air through the vents to dislodge the stubborn stuff; so that I can shop vac it out in one (or two) events? I like the idea, but don�t want to force anything loose. My compressor goes up to 150psi. But I suppose I could dial it down to something really low and start there? thanks

Thanks for this wonderful, clear tutorial. Using this thread I made a little video of employing your method. I hope others find it of service. You Tube Stazza

Quotes source post: 17345491

Great video, but I would remiss if I didn't mention, there's a while other flap that most likely is in bad shape as well. It controls where the heat/ac blows. So don't be surprised if you still have black foam coming out. It would be that flap.

Hey Stazza, This is great. It really doesn’t look too bad. I’m think I’m going to give it a shot! cheers!

Quotes source post: 16443868

I would think that if you used aluminized HVAC tape you could install it without pulling out the door flap, instead of replacing the foam strips as shown above in this thread. /X3

please email me at [email removed] I would like to visit with my 987 and have perform this Job. I live in Houston but often travel to SA to visit parents. 2813009623 please confirm as soon as you can.

Great write up I just I was not 10 thumbs guy hey deporto what would you charge if I drive up to you to do this job or do you have a local shop you could recommend thanks Mike

Well I�m 80 years old, and with the help of my younger neighbor next door, it took us about 6 hours over a 2 day period to do the air flap from the frunk. Getting it apart was slow as we followed the instructions we found on Reenlist. Putting it back together took about an hour as we knew from taking everything apart, how it went back together. I wouldn�t want to fo it again as i have arthritis and a bad back from 5 operations. I still need to take out my double din radio and repair the flap straight back which I understand isn�t as bad , just fiddely to clean( without removing glap) and attaching new tape. I only have read about the fellow in Florida that does all this, and I�d have to look thru the articles in Rennlist to finc him again. He does the front job in about 4 hours. Maybe if you could find him , he might know of someone closer that could help you. Dsve

So, last fall I did this foam repair on my �03 996 cabriolet, and it went beautifully, and at 80 years old, if I can do it, most others should be able to do it. Works great, especially if they, like me, go by your directions.Now, I need instructions on the other flap behind the center console. I�ve previously installed a double din pioneer entertainment module. I�m ready to tackle the other flap, and it seems someone made an instruction post on this, and I can�t seem to find it. Any help on doing this other flap fix would be greatly appreciated. Thanks, Dave

So, any instructions on how to get to the other flap? I�ve done the other on last fall. Thanks. Dave

You Tube

FWIW,,, the aluminum tape comes in a variety of thicknesses all the way up to like .020" I've used the heavy stuff to repair the attaching point on the body of a sports 2000 its almost sheet metal. The professional stuff from a HVAC supplier is 100% better than the home depot tape.. There is also some that has a thin foam under the aluminum its designed to go INSIDE an industrial duct to prevent whistling. "Duck" or Duct cloth tapes the adhesive eventually dries out and the tape shreds. If you can find "100 Mile and hour" duct tape it was designed for aircraft skin sealing and the material is non water permeable. Haven't seen it in a long time.. You can also buy silicone rubber sheet that has an adhesive on it, comes in 2'x4' sections used to seal surfaces around chimneys and such its very thin and tough, black and has a vicious adhesive, cuts nicely with scissors. Back peels off, Believe you'd look to roofing suppliers.. Believe its also sold to repair membrane roofs on commercial buildings.

I did the repair today, thanks AMCPILOT for the guidance. It took me 4 hours from the time I walked downstairs with my coffee, to the time I drove it out of the garage. Notes from the repair (02' Cab C2): I should have lowered the windows before I disconnect the battery. Grateful that I moved the seats back before I disconnected the battery (thanks F-Lambda, this should have clued me in on my cab windows) I used DynaMat and aluminum tape to replace the foam. Also, reused the foam strip that was still in great shape. I used wine corks rather than the hose pinchers, as the corks stayed out of my way When pulling/reinstalling the heater core, I covered the hose pipes with my thumbs to keep the antifreeze in the core. Some of the time was spent cleaning and installing a new cowl. All in all, a pretty straight forward project with AMCPILOT's guidance.

Quotes source post: 17546098

I myself removed the dash and the ducting to get at both flaps. There was one member that removed the radio and center stack and then cut a square hole in the ducting to create an access to the flaps, and then made a panel to cover the hole. Alot simpler than removing the dash. Another member I think was able to partially recover the second flap from the bonnet, but the only way to get good access is from the dash.

Quotes source post: 17549282

Check my post up a bit in this thread. I covered how I fixed both flaps through the heater core. I was able to cover both sides of the 2nd flap. All through the heater core, didn't need to pull the dash, just a few scrapped knuckles and good to go.

Omg I wish moxie was close to me I would pay to have do this no one in my area has a clue

*deleted*

Quotes source post: 16441232

is it a must need to modify the pivot flap in order to complete this

Quotes source post: 16453194

Hello AMC Pilot. Where are you located. Could I bring my Porsche to you to repair the foam problem? thanks

I�m in Bedford Texas. And it took me two days and help from my next door neighbor to do ghis job. And I�m 80 years old. I used the photos in the Rennlist to do it and it worked out just fine. If you do ghe same you could do it as well just take your time. Then , theres the second baffle to fix, which is straight behind the radio unit ,and it�s much easier as you can repair the baffle , leaving it in place. Theres also a photo help for fhat in Renn list. If you can�t find it I took a few photos i can post. I think i did post them. Let me know.

Also in the Rennlist,somewhere there is a guy in Florida that can fix the bsffles in about 2-3 hours. See if you can find him.

Why is this not a thing on the east coast yet WINTER IS COMING please I need this done lmk if you know anyone who can NYC area Mike

Thank you for the great write up. I followed the procedure, my foam was still intact for most part but was starting to get deteriorated. SO I removed the flap and cleaned it up and covered it with new material. Put everything back but the heater is not working. I verified that the actuator motor turns when I change temperature, verified that hot water gets into the heater core (hose is hot). The heater core seems to be intact with no leaks. Also, the heater was working very well before I started the procedure. Do I need to calibrate the actuator motor? What is the position of the flap when its set to HI heat? Thanks again for the help.

Just completed this job. Roughly six hours, taking my time. Much appreciate all the tips and pics. Especially the bottom clip info. Wine corks work perfectly in the heater hoses. Plugs or stoppers would be perfect for the heater core pipes. The majority of my coolant came from there. Be nice to plug them immediately after pulling the hose. I used half a hacksaw blade slightly bent held by vice grips so I could stand by the drivers side tire and cut the plug top off in about 30 seconds. By hand would have taken me much much longer. The upper plug is pretty straightforward as you can see the flap orientation. I increased the plug bevel with a file where the flap goes into the plug to increase my chances of it going back in. The lower plug is a PITA. I put a level stepping stool the same height as the seat just outside the door so its a little more comfortable. Im 6'-2" so getting in there is hard enough and once im in there there is no room to move around. Honestly think removing the seat would be easier. The levers disassemble very easily. I put the plug screw back in most of the way and was not having any luck extracting it, so I just grabbed it with pliers and gave it a firm yank. Came right out. The grease prevents grabbing the plastic. I also increased the bevel on the lower plug. With a Dremel. For lower plug reinstallation I attached the lever snuggly to the plug (it only fits two ways) then closed the flap in the frunk and stuffed a towel in there so it wouldnt move much. Also a screw driver to help center it in the lower hole. Handling/orienting the plug with the lever was much easier, popped right in after a few gentle tries. Also easier to see about what angle it should be. This lever just snaps into the next one. Could never even attempt this without all the great write ups pics and tips. Thank you all! PS - test drove today and . . . . . I HAVE HEAT !!! Was a little concerned because I used foil ductwork tape x3 or 4, not foam and was thinking maybe it might not seal, but its fine. I think my directional flap is shot too, but I can manage by closing the midlevel vents on the dash to get defrost.

Quotes source post: 16444120

For $75 Ill fly you to S.Fl for the weekend and put you in a hotel and buy you lunch and you�d still be saving me $$.

Thanks Amcpilot for your detailed �how to�. Right hand drive cars have the added complexity of having the hvac system mirrored and also an ac pipe running directly over the top of the heater core inlet/outlet. The mirrored hvac issue was rectified by mirroring all the photos i could find! However my ac system had to be degassed to enable removal of the pipe so I could get the heater core out. From there is was all straight forward like you described. As a stretch target, I found a method of also replacing the the foam neatly on both sides of the second vent door. Let me know if this is of interest and I will post some pics and a description.

Quotes source post: 17815887

This is of interest. I would like to see what/how you did this as I'm about to take on the project.

Of interest! OF INTEREST!!!

OK no problem. I'll get some info together and post it probably on the weekend. WIll let you know.

Quotes source post: 17542059

Any idea who the fellow in Florida is? I have an �09 that is spitting at me.

May I ask those who completed this task last year and uses their heating and AC system regularly, do you smell the replacement foam that you guys used or any other smell? I think the reason why Porsche uses the open cell foam is to prevent moisture trapped in the system and thus turn into those moldy smell, open cell foam allowed air to flow through and help keep the inner HVAC system dry.

Hi hoofdpijn and jobyt I've posted the how to for the innder vent door on a new 996 forum thread called: "Repairing the inner vent door black foam issue". Good luck and let me know if you need more explanation. Regards Simon.

..

Thank you! I had the exact same problem with the lower plug as far as getting it out as I was struggling to get it loose. Your pictures allowed me to understand exactly what I was dealing with which made a huge difference. After a bit of a struggle trying to pull it out with various tools, I screwed the screw back in then used needle nose pliers and pulled straight down and it came out.

Quotes source post: 17720788

Did you get an answer to this question? I'm in the middle of doing this, and would like to make sure things are in the right place and the flap moves correctly before I put everything back together. Thanks! -Mike

For anybody interested, I designed and 3D-printed a cap to put over the flap hinge instead of using the original, cut-off piece of plastic. I've attached the STL file if anybody wants to print it. Just remove the .TXT extension after download. I printed it in ABS. Cheers! Mike

Crazy estimate to repair!

What THE F…. 6500 for a 4 hr job

I’ll do it the two Rennlist methods for just $2500.

Just did this and the entire time im laughing to myself thinking about how the OP charged $75 for this service 😂😂😂😂

I did this job today. Very helpful post. Thank you!

Quotes source post: 17972091

Wanna do another?

Quotes source post: 17972129

Haha. Compared to AOS it�s not bad. Hardest part was lining up the upper bent door tab on reinstall. The hacksaw approach didn�t work for me. Ended up using a dremel to access the upper bent door tab. The lower tab was very easy to access. I found it easiest to just remove the arm that attaches to the lower tab. That way the tab was already lined up for reinstall. 1/2 day project as a first timer. The steps and pics were very helpful to me.

I wish there was someone near me who would do this

This job is punishing. 2 days after completing this my passenger side rear window regulator failed (01 cab). 996 = pain and punishment

Quotes source post: 17972238

I hear you. I found it helps to have two as one is always on a lift.

Quotes source post: 17972201

I'm up in Albany happy to do this for you! Maybe buy me a beer and a meal?

Quotes source post: 17922524

That's why they are called "STEALERSHIPS"

Quotes source post: 17977366

How about for a flight to Miami and a hotel room?

Dranon that would be a pleasure I have a place near me that’s got the best Italian food on the planet and a steakhouse that makes phenomenal beef Wellington

Quotes source post: 17972238

Really? I didn't think it was that bad all things considering. It was the first time I had touched any of this stuff on my 911 and I think it took me about 3 hours. It is a pain to get the cap off the top to release the door. What worked for me was a sawzall blade used like you would see lumberjacks on a giant tree saw back and forth. The actuator arm on the bottom tripped me up because I didn't take a pic of how it went in and it was disorienting since I was upside down. I ended up putting it on wrong and had to remove and reinstall it. I will say it's been something like 2 years and it's still holding up great.

Quotes source post: 17977399

Ha Flying into Miami next month to go scuba diving in Key Largo! THen up to Deland for Skydiving! I doubt my gal will put up with me working on a car though!

Gotta wait til it gets a little warmer!

No worries just lmk my car is stuck on cold anyway and I don’t drive it in the winter but again much appreciated I hope to see you after a couple of months

Quotes source post: 17978018

Ill lend her the jet skis for the day! Enjoy your trip!

I can do it both ways so just let me know which one you want through the dash behind the radio or through the frunk behind the battery

Dranon which ever is easier I have a single din radio and amp and a place to work ion it that’s off the street

Quotes source post: 17977397

In this case the "stealership" is quoting the price to pull the dash apart and, probably, replace the heater box assembly completely. Looked at in that light it is a wee bit less usurious.

Thank you AMCPILOTAMCPILOT ! I just finished this project but would not have attempted it without your fine tutorial. A few things 1 - Allow plenty of time. A person with experience may be able to complete the project in just a couple of hours but it seems wildly optimistic to think a first timer could be that quick. My project was complicated by also covering the inner vent door (following this tutorial Repairing the inner vent door black foam issue - Rennlist - Porsche Discussion Forums ) and I readily admit that I may be slow but even so it took me -far- longer to complete. 2 - Loosening the coolant fill cap in the rear trunk releases any remaining pressure in in the cooling system and so can minimize the amount of coolant lost when the hoses are disconnected from the heater core. Wine corks are just the right size to plug the disconnected hoses. 3 - Another alternative material for covering the blend doors are craft store self-adhesive EVA foam sheets. Although I make no claim that this is the "best" choice I like the idea of covering the doors with fewer, larger, pieces of material instead of using a bunch of narrow strips. EVA foam sheets cut to size Applied to outer blend door Photos of my project here; ProjectBoxster7 | projectboxster (rx19jones.wixsite.com) Cheers - dj

I chose to use HVAC foil tape.20x more durable than foam. Why use foam? Little bit of residual airflow throughput? I poked a few holes in the tape to allow for that. My heat works great. And once again thank you all for posting all this info that I couldnt have fixed it without!

Quotes source post: 18003166

Because that�s what the engineers who designed it did. Yes indeed!

Quotes source post: 18003281

I typically love German engineering, but in this case I wish they would have used foil at the factory. Would have saved me some grief, $, and a Saturday sitting in my frunk. Ha. Oh, and the garage yoga gymnastics fitting my large frame into the pass foot well. AAAArrrrggghh!

HVAC tape certainly is more durable than foam but it was an option that Porsche decided not to use when they built the car so I tried to see if I could determine why. While working on this project I came to the conclusion that covering on the blend doors serves three purposes. The first is (well doh) to cover the holes in the doors. Any type on tape or foam or plugs could do this equally well. The second function is vibration dampening. It seems that air blowing across a piece of sheet metal has the potential to cause an anoying vibration. I don't know if this actually occurs in the real world but foam would be better able to damp such a vibration than tape. The third function is less obvious but probably more significant. When I removed the outer blend door and examined it, I noticed that the original foam covering extended about an eighth of an inch beyond the edges of the door. My guess is that that is meant to form a seal around the door's edges. The EVA foam I used came in 12" x12" sheets and that made it easy to cut out pieces that both covered holes in the doors and duplicated the seal around it's outside edge. Don't think I could have done that with tape. Another material that may be more durable and still seal around the edges and dampen vibration would be self-adhesive felt sheets. Didn't think of that one till I had my car put back together... Oh, and I don't buy into the "they used foam so a little air can pass" theory because the original foam on my blend doors appeared to have a coating to make it airtight. cheers - dj

Quotes source post: 18003281

I used the HVAC foil as well, worked like a charm. Lol the same engineers that spec'd a degrading material.

Quotes source post: 18004233

But ecology!

Finished mine last Sunday - was able to get to both doors; the hot/cold door came out exactly per the instructions, and I have the bruises on my wrists to prove I was able to reach the level door in the box to replace the foam (in place) as well. Thanks a million!

Thanks for posting this. Would the missing foam effect the ability to cool the car or just heat it? Does anyone know if there is anyone on the east coast that is doing this repair?

Hi, It depends on which door the foam is comng from. However it is more than likely some is coming from the hot cold mixer flap which means the air can flow through the heater core which is always on. So, yes, your heater will always be on. Your a/c when running, will be fighting against the heater and probably not winning. It is a job you can do yourself, sepecially if your car is LHD since you won't have to remove the AC pipe like us RHD owners do. Here is a link to a post I did when I completed mine earlier this year. Some of the photos come from trailblaizers before me. I just added to them, made RHD versions and added instructions for the inner vent door fix since they are both probably in bad need of repair and you may as well do both at the same time: https://rennlist.com/forums/996-foru...oam-issue.html

Has anyone used these? Seems like a novel solution: https://www.ebay.com/itm/17472328381...mis&media=COPY The item description states: � Has been tested on Porsche 911 996, and Boxter 986 air distribution boxes.�

Quotes source post: 18226928

I am sure it would work fine, feel like if you've made it far enough to get access to the box you might as well pull the flap out though. As long as you can get access to all the holes it should work.

Quotes source post: 18182346

Your a/c when running, will be fighting against the heater and probably not winning. What if my ac blows cold? Mine is blowing thin foam shards out, nothing horrible. If I have good AC, should I do the repair or just let it erode until, out of sight out of mind haha. I've never had the heater on, live in the south...I do have heated seats icoe.

Quotes source post: 18228742

One thing in my mind was the fact that I was probably breathing some of that crap into my lungs. Getting it out altogether made me sleep better.

Quotes source post: 18229325

Can't argue with that. Tho, my lungs have seen some rough times. Speaking of, I've been watching some detailing YouTubers lately, and they seem to like sniff testing the chemicals. "This smells nice!" Years from now, they'll regret their curiosity. I hope I'm wrong of course.

Good one. Not bad at all I Did the one at the heater core already. Now time for the inner one. Thanks

Which one would I need to do to keep the damn front windshield from fogging up?

For windshield fogging set the AC to floor only, you should still get airflow out of the center vents but it should stop it from going to the windshield.

[QUOTE=AMCPILOT;16441232]Did another repair of the �black foam coming from vents� repair on a clients car today ... this also causes loss of the ability to heat the interior too, since the foam loss allows cold air to come directly in through all the holes in the vent flap as shown. I do this repair a lot as all 996, 986, 997 and 987 Porsche�s will suffer from this issue. here are some photos of how to do this repair ... hope it helps some facing this issue. Check out this and other projects at my Instagram page #joeslastchancegarage Removing the wiper mechanism ... as you can see, I�ve already removed the wiper arm, the cowl panel and the battery to gain access Removing the strut brace to get access to the heater core area ... note I�ve already removed the main strut brace bars in this photo Remove this rubberized panel by gently pulling up at the edges to separate from the sealant ... don�t rip this panel so take your time Clamp off and remove the two coolant hoses ... use some paper towels to catch a little coolant that comes out ... should not be very much if you clamp the hoses as shown Remove the heater core This is the only �mod� ... carefully cut off the top of the flap pivot housing ... just about 4 mm is all you need to cut off Here it is with the top 3-4 mm cut off and you can see the flap pivot This is the flap pivot removed ... just use a small pick to carefully pull it up and out Removing the lower flap pivot ... it�s only help on by a single screw and the flap motor pivot and then pull down. Reach in and remove the flap Flap coming out ... note all the foam has fallen off and most came out through the vents ... the �black foam� apocalypse every 996, 986, 997 and 987 owner will experience at some point Flap fully removed and note all foam gone ... these holes allow cold air to come directly in, preventing any heat inside the cabin. Remaining foam removed from the heater core box Foam adhesive also removed from heater box Replacing lost foam on the flap Replacing the lost foam Me replacing the lost foam This is what it looks like with the flap repaired ... I put foam on both sides as the factory did, but this foam should last much longer Vacuum out any remaining foam in the heater box ... there could be quite a bit Reinserting the flap ... it is critical to ensure you put it back in the exact orientation that it was originally in ... it is easy to put it in backwards and if you do that, it will not function correctly Put the flap pivot cap back on once the pivots are reinstalled ... I use black �dum-dum� to hold it on ... works great and avoids problems using glue or epoxy fouling the pivot. Now just reverse the steps above to reinstall everything. What steps are taken inside the cabin? I can see all of the parts that need to be removed from the cowling, but did not see the steps necessary to remove screw attaching flap inside car.

Hemiking when are you coming to ny I have 3 others as well

@Hemiking How long does the job take a competent wrench to do, in case I can convince my Indy to do this work for me. I'm just curious how many hours I should be estimating..

Quotes source post: 18251104

Did you read all of this thread? Like my post 45?? And there are other posts just after that descrbing some better refinements. https://rennlist.com/forums/996-foru...l#post16454725

Quotes source posts: 18251114, 18251158

Guys, those aren't Hemiking's pictures. He didn't do it. He just reposted the entire first post of this thread from AMCPILOT. AMCPILOT posted the how-to and pictures. https://rennlist.com/forums/996-foru...l#post16441232 He did ask a question about the interior, which I hope my earlier post answers.

Hi all, I made this little video a year ago using AMC pilots technique. I�m not a professional mechanic, so hopefully my video will give other amateur enthusiasts courage to do this on their own. I was SUPER slow and careful as to not break anything - I also cleaned everything as I disassembled the car. I took my time (and filmed it) and took me 4-5 hours. I could do it in 2 hours easily knowing what I know now from doing once. Hope some of you find this helpful: You Tube

Quotes source post: 18251114

How far are you from JFK?

40 minutes towards nj right next to the Verrazano bridge

I'll be down on tuesday to pick up my GF from the airport. can do it before I go get her!

Omg yes please dinner on me I’m pm you my number

Any thoughts on using this tape: Amazon Amazon

I�ve been living with this for awhile. Foam everywhere, but the A/C and heater still work. Wife opened the closed passenger side vent today and got a face full of foam. While it was funny to me, I guess that is a sign that I need to tackle this job.

Quotes source post: 18259025

You and I both.

Quotes source post: 17922524

that�s f�ing gross. Shame on them!

Quotes source post: 18259927

I don't know if someone already said this back in January in response, but I think that the "book"-method to repair these flaps is to remove the entire dash, remove and replace the entire ductwork assembly, and reinstall everything. I suspect that is what this quote was for. It is pretty excessive ludicrous. EDIT: clarified my opinion!

It’s obscene and the reason dealership’s deserves a bad rap

Quotes source post: 18259935

you are correct. here is the procedure divided into 3 segments, in case someone would like to follow it. I made this write-up back in 2012 when I bought my first Porsche (2001 Boxster S) with a leaking evaporator. step 1. heater core removal. https://www.dropbox.com/s/6bi2dlsy47...moval.pdf?dl=0 step 2. dashboard cover removal. https://www.dropbox.com/s/lcthesknyn...moval.pdf?dl=0 step3. evaporator replacement and flaps re-foaming. https://www.dropbox.com/s/gja11v6yi6...ement.pdf?dl=0

Quotes source posts: 18228742, 18259043

After converting my .1 to the .2 A/C vent so I could fit that leather horseshoe and install the .2 cup holder, I�m very comfortable with taking out everything to get to the flaps. I�m going to use the method of cutting the duct to get to both flaps. Hopefully, I�m a pro at it by the time you get back!

That estimate makes sense. To have factory trained technicians perform a factory quality repair the way the factory said to do it. These might be $25k cars now but they weren't when new.

I guess I will have to tackle this next. Will see how this goes..

Quotes source post: 18260953

yeah, 100% this. The expectation that the dealer would do a hack job (not that there is anything fundamentally wrong with the way people are doing it here) for a couple bucks is simply unrealistic. You go to the dealer, you get what the book says. No surprise.

Quotes source post: 18279299

My nearest dealer, and I'm not in the most expensive area in the nation, charges $250/hr for labor and the book says a battery install is a 1 hour job. They are also running an oil change "special" for $399, except by the time you pay the overage for a car that holds 9 quarts + tax you're at $500 LOL!

You should move to where real humans live lol no seriously move

Sweet! SUPER Sugar Crush. Downloaded. Thanks.

Quotes source post: 18279635

Overage? Is the special for up to a certain amount of oil?

For all of you in hot climates, covering the flap holes back up made a giant difference in how well the cold AC worked. Much more air flow and noticeably colder! I saw a few people say it "should" make a difference, but I wanted to confirm that is definitely makes a difference.

I have read that someone is using DSP plugs found on eBay. The look like a very clean and easy repair. However my concern is will the vent close enough or would it need the form tape on the vent door edges ?

Finally got around to this today, took longer than I expected but overall wasn't that hard. Once I removed the first duct/flap, I was able to see the second one, it too was missing all of its foam, but there was no way I was going to effectively get to it. Does any one know which flap does what; my biggest issue was in the summer the windshield would fog up from the A/C being on, I am hoping this fixes that, but have to wait until next summer to find out. From reading all the posts and watching the video/s this was the list of pointers I came up with that made the job easier: � Run heater at full and use shop vac to suck out as much foam as possible before starting � Use masking tape on windshield to mark where wipers are located; I also used some on the edge of the hood, I also replace the black cowl under the wiper blades, I figured since it was out I would swap it since it was faded and plastic restore wasn't cutting it anymore - note if you are replacing the cowl, there are a few parts that have to be transferred over, and there is an extra wire over by the cabin air filter, not sure if that is a 997.2 only thing, but watch out for it � Loosen coolant fill cap in engine bay, this relieves pressure on the system, for less fluid loss � Block hood latch with towel; this is key, throughout I had to put the hood up and down to get the wiper blades arms and cowl out � Lower windows before you remove the battery � Pinch off heater core hoses, you can use wine bottle corks or �” socket extensions to plug the hoses � Have towel for radiator fluid, and clean any up that spills; I had spilled more than planned, and had some pre-mix to fill the heater core back up � Photograph the flap position, triple check, it should move freely once installed; also photograph the lower motor lever arms before removal � Use screw to pull on the bottom plug, I also used a plastic trim pry bar tool to pop it, and used the same to push it back in � Run foam around all the edges, there is enough clearance room � Regrease pivots transferring parts from the original cowl to the new one Still had the adhesive all over, but no foam left... ready to go back in!

So I've got the black foam coming out on new to me 1999 with 99k miles. I was pulling some out with tweezers, when I pulled this out --- Did I pull something unrelated to the foam covered plate? It came out without much resistance, so I didn't know what it was till it was near opening of vent (passenger).

That is another piece of foam on the blend door. It is a strip along the edge to seal against the fitting to prevent air leakage. When I did my blend doors I just glued it back on but most people dont or it deteriorated on them! Thats where it was!

How exactly did you use the dum dum to hold the flap pivot cap on. Did you use a bead between the cap and the stem or did you put the pivot cap on and then put the dum dum over the entire cap and down the stem to hold it in place. thanks.

Quotes source post: 18535783

I suggest the latter. You don't want to interfere with the pivot itself being able to move, you just want to hold the cap on. I think I found a plastic plug that fit over the top of the tube and used that to keep stuff out.

Quotes source post: 18535783

the latter.

Quotes source post: 18382910

I'm getting ready to go this route. It seems really neat, based on this guy's video. We'll see though, I guess. You Tube

There are threads on here about that method of fixing the second internal door, and if you're using it, you should search for them. I think some have been a little more elegant than his cutting. But all involve cutting. Pedantic aside: I have an issue with his using RTV. RTV is a sealant, not an adhesive. He really wanted an adhesive here.

i think he made a pretty good case for just using the alluminati tape

Quotes source post: 18538836

Yeah, I don't know that the oscillating tool is how I'd go at it, but I was thinking something more along the line of 3M Windo-Weld rather than RTV. If that stuff is good enough to stick the windshields on supercars, and hold up to the elements, it should be A-OK in my 996's heater box.

Quotes source post: 18538600

So this is a Boxster fix and not a 911 fix?

Quotes source post: 18541133

Boxster(986) & 996 are similar.

I think I'll use that method (cutting from the interior) when I get around to fixing mine. I have to remove my radio to troubleshoot a problem with my bluetooth adapter anyway.

Quotes source post: 18542796

In order to fully repair the blend doors you need to do both methods. But neither method is extremely difficult. The through the frunk will allow you to fix the outside/recirculate blend door. The behind the radio will allow you to fix the defrost/mid-vent/floor blend door. Allow ~1 hour for each method.

The question that keeps coming up in my brain is: Why did they use foam in the first place? At first I thought it was pressure equalization to allow the doors to move if the fan was on high. But then we have examples of tape being used which would kill this effect. In the case of new foam, it has an adhesive layer that would cover the holes and create the same problem. Now we have these plugs, printed to fit. And all cases seems to work well. Was the foam for noise suppression? Maybe none of us will ever know as we all seem to have bought these cars after the foam was already failing. Maybe the holes in the doors + foam is lighter than a solid door? What is the design in the new cars? Sorry for the silly post. Hopefully this question will bug someone else as much as it does me...

Yes, I've wondered the same thing. They didn't just use it at Porsche. VW and Audi have similar foam on their blend doors. Perhaps manufactured by the same 3rd party?

The foam is for sound deadening. And it's been an issue since the late 80's. I have fixed many VW Mk2/Corrado heaters by renewing the foam. My Cayenne is having the same issue as well.

Two days ago I ordered two of the eBay blend door cap kits . I will repair my Boxster and 996 . Not really looking forward to the job but there is enough info in this post and others to get it done . My Boxster has decent heat but the 996 has none ☹️ . AC for whatever reason works good in both cars .

While you're in there, can you test if the blend door is magnetic? Looking through the post it at least seems possible to access the doors through the vent without cutting it open, if you had some sort of designed tool to get in there. Cutting some magnetic strip to size would be a nice approach if it will actually stick to the blend door.

Quotes source post: 18543139

I dunno but apparently it's not just a Porsche issue. This foam blew out of the defroster vent of my 2001 BMW this morning. First time I've seen it since I bought the car in 2015. I'm afraid to Google what the fix is.

On a side note, my Bluetooth issue fixed itself yesterday. Maybe if I wait long enough, the foam problem will do the right thing too.

Quotes source post: 18544832

Hey! My PSE issue fixes itself too! So it's just a matter of waiting long enough?

I created and 3D printed a new cap for that top post. For those with a printer, here is a link to my file, with a photo of the cap installed. https://www.thingiverse.com/thing:5762502

Quotes source post: 18544386

It's bare aluminum.

I have a feeling i will be needing to do this soon as I found a few pieces in the vent recently..

My 04 C4S cab has been blowing chunks of foam for probably 4 or 5 years. But the heater and A/C always worked, until the fall of 2021 when the heat stopped suddenly. The A/C has and still works fine. I asked my indy mechanic to investigate when it was in the shop in January 2022, and he said the only fix involved removing the dash for $6k. He did say that if the heat were set on "Hi" then I'd get heat. He was correct, but on "Hi" it gets REALLY hot in the car. I saw all the threads and videos about the two approaches to address the blend flaps or dampers, and decided to address both flaps so I'd go in behind the radio and cut the duct. I did so (a sharp box cutter worked well, and left a cleaner joint than I think my oscillating tool would have) and installed the 3-D printed plugs available on e-bay. I filled in all holes on both flaps, but I still don't have heat unless I set the unit on "Hi". Very disappointed!

Quotes source post: 18578412

This method is detailed in a video linked to in post #207 above. I think I'm going to tackle this through the frunk.

Quotes source post: 18578412

So you are saying you were able to reach BOTH blend doors from inside the car ? Everything I have read says this is not possible . I believe ( but could be wrong ) that to repair both blend doors you need to attack from inside the car behind the radio AND from the front trunk . This may or may not be why you had less results than expected .

I just completed this repair over the weekend for the blend door accessed by removal of the heater core from the front. Turned out great. Heater works like new.. Little bit of a learning curve but nothing that some time doesn’t help with…

Interior access through the vent gets you to both doors, access through the heater core only gets you one of them. Good to know a box cutter worked for that.

I followed the method shown on the video on post 207 above (that's on a Boxster, but pretty similar). The first flap I came to (closest to rear of car) has four oval shaped holes. I think this flap directs air up or down within the dash. The second flap (toward the frunk) has (IIRC) 16 round holes of two different diameters. The second flap has a bend in it, whereas the first is flat. I think its the one that blends hot and cold air . I installed the 3-D printed plugs with the gasket material recommended in the video. I think this weekend I'll take everything apart and observe the movement of both flaps when I work the controls and have the engine running to get some heat. I know the first flap rotated along with the up and down HVAC buttons, but I'd like to see if the second flap rotates when the thermostat is exercised up and down.

There are 2 blend doors in the 9x6. They are both "L" shaped. By going behind the radio you can access the entire "L" of 1 blend door in-situ. The other blend door(Yet another "L" shaped door) must be reached(and removed) from the frunk. Door behind radio controls air flowing from defrost/dash/floor. Door under heater core(frunk access) control airflow from outside/recirculate and heat/cold Complete repair requires both doors to be repaired. Partial repair may work for some...for a while.

Yet, there are two doors that can be accessed from behind the radio. How can this conundrum be resolved??? Notgonnalie�really hoping to avoid going in through the frunk.

From what I've seen, you can get to both doors from the dash, but you'll have to change the direction of flow so they move around for access? Haven't done it yet, will find out.

Perhaps I'm wrong and you can reach both. But I didn't see the one below the heater core when I was behind the radio. But doing both ways was not too bad actually. To put it in perspective from easiest to worst: Oil change -- Motor mounts -- radiator cleaning -- deep sump -- blend door via frunk -- blend door via radio -- center radiator install ------ AOS ------- Rebuild M96

Quotes source post: 18579181

That's exactly right. I was able to reach both of the doors through the dash. The front door moves when you adjust the cabin temp between hot and cold. You Tube

I did this couple years ago. When I had my dash out, it was simple to reach both blend doors. Super easy to do this from behind the radio. I used metal tape rather than foam.

Good to hear that you can do both through behind the radio. I used metal tape with foam over it and around the edges of the blend door. It seals MUCH better now. Also one of the dash rattles I had was resolved.(I credit the foam on the edges)

After two winters with no heat (luckily I've got heated seats and FL does not get too bad) I finally got around to tackling this in December. I used a different video tutorial than most of you are posting, so this may help some of you. I think it provides a little more detail in showing how the blend doors physically move to access the door closer to the firewall. You Tube

Just wrapped up the repair using the 3d printed plugs and it was honestly not that bad. The worst part was cleaning the foam and residue on the doors. In hindsight, mine weren't that bad, and I'd probably leave it until more of the foam had deteriorated. We'll have to see how it affects the heating and cooling now, but this is definitely not something to be afraid of tackling if you're on the fence.

Quotes source post: 18585532

What adhesive if any did you use on the plugs ? Or do they actually snap in ? I bought two sets of plugs off fleabay for my two cars but haven't attempted the repair yet .

Quotes source post: 18585538

I had purchased RTV to use but after snapping one of the plugs in, and trying to pop it back out with my fingers, I opted to just put them all in dry. The fit feels plenty strong, and if it's not and I have to go in and do the job again in a year or something, I'll probably either buy some panel bond or some window-weld to stick them in.

Quotes source post: 18585532

Did you approach from the front or rear (that came out wrong - oh well).

Quotes source post: 18585545

Did you repair both doors ? If yes did you access both from inside ? Thanks

Yep, did both doors by going through the interior of the car with the radio out. Wasn't super challenging, but I did have to move the doors a bunch to get everywhere, which if I wasn't a giant human with big hands, I probably wouldn't have had to do so much.

Quotes source post: 18585569

Thanks for the follow up answers , very helpful . 👍

I have a 2002 Carrera 4 Cab. To get at the screw in the bottom of the duct holding the lower bushing, I have a large, carpeted, kick panel in the way in the passenger's footwell (houses some plastic box with wires connected to it). I was able to get the 6mm screw out at the forward end of the panel, but the back of the panel is held solid. Anyone know how to free up this panel? Thanks.

Quotes source post: 18646608

The plastic box is your subwoofer. When you pull it out, flip it over and check the condition of the speaker cone. If it's bad, it can easily be replaced versus buying an entire new subwoofer from Porsche. The same woofer is used in a Mercedes R230 and can be found easily and cheaply on eBay. Just search for the Bose part number. There is also a drain that runs directly underneath it. Ensure it isn't clogged. In order to remove it, there is one additional screw towards the rear of the car (you have removed the front one). The screw is located sort in the middle of the box. You will need to peel back the carpet trim piece a bit to uncover it. I don't have a great picture, but in this link you can see at least what the box looks like removed: https://www.redlineautoparts.com/por...SABEgI11_D_BwE

Thanks! I was able to get it out with your help..

Quotes source post: 18646608

Glad to hear you found the second screw! That thing bedeviled me for hours before I finally pulled the carpet back far enough and found the dang screw.

What is the preferred foam for the job. It looks like @AMCPILOT uses a frost king brand. I picked up Frost King Available V447H Camper Mounting Tape 1-1/4-Inch by 3/16-Inch Frost King Available V447H Camper Mounting Tape 1-1/4-Inch by 3/16-Inch . Seems similar but not exactly what others in this thread have used.

Quotes source post: 18655934

I did exactly the same thing (found it at Rural King) and had the same concern. Seemed adequate, but I could peel it off with some effort. I cut a piece of aluminum step flashing (under a buck at Lowes), scuffed both surfaces and glued it to the flap with a film JB Weld, let it set overnight. I tested several adhesives to improve the adhesion of the tape and found what worked best was just a light skim of liquid CA glue, then peal and stick the foam -very secure. Be sure to wrap the foam around the edge of the flap to fill the gap. Works great. I'm indebted to AMCPILOT and others who perfected this repair method..

Quotes source post: 18655934

I made a video documenting my process, and I used this product with good results: Amazon Amazon heres the video, in case it helps: https://youtube.com/watch?v=FaKw9BxF49Q&si=EnSIkaIECMiOmarE

I used Dynamatt on mine since I had a bunch of it from a project. Sticks really well and should outlast the car

Quotes source post: 18657487

Any concerns or experiencing the smell of the butyl adhesive backing on the dynamatt, especially when the heat is blasting?

I used this stuff. Home Depot. Mold resistant which sounded like a good thing.

Quotes source post: 18657524

Haven't noticed any. There was a strange smell that went away after a few heat cycles. I replaced the heater core while I was in there since it wasn't a terribly expensive part and I figuired I might as well. I think it just had to go thru a few heat cycles to burn off whatever coating is on the metal from the factory.

With the help of this tutorial and my trusty Bentley manual, I successfully performed this repair today. Biggest problem I ran into was that I managed to drop the plastic �upper pivot� down into the heater core box. It then rolled right through the opening to the evaporator and disappeared. After much muttering and cursing, I finally retrieved it with my trusty Harbor Freight grabber tool.

I used A/C aluminum foil on mine and there is a little more noise coming from the AC vents. I guess that is the reason why Porsche covers the aluminum doors with foam. But I'm happy to have cold air again and the heat also works great. I was able to apply some tape to the 2nd door front and back, but couldn't do a tidy job like the 1st door, so I'm also not getting any air leakage between the floor/front/window vents.

After a few years of ignoring the problem I fixed the "Black foam problem" in my 2001 996. The only problem I had was removing the lower flap pivot pin. Despite pulling it down as hard as a dare I could remove it from the passenger footwell until I tapped it from above with a long screwdriver. A light tap from above was all it took..

Thank you so much AMCPILOT for this excellent tutorial that has helped so many of us! I think I know why some widebody folks think that their lower clip is different: they are messing with the slot for the under dash foam and not the right piece. I have a C4S and did this job today and of course, I couldn't get the lower clip to budge so I assumed it was "different" because it was mentioned in a few posts here, it isn't. It looked like someone had removed the 6mm bolt and plastic spacer so I kept trying to get it removed, when it didn't come loose I assumed that I could remove and replace the door from above (as I saw others do.) I snapped the head off of the bolt that holds the piece in because I tried to force the door back in place (correctly aligned with the slot of corse) and broke the head off. Then it became very clear to me which one I should have been working on. Good luck all...

Quotes source post: 18749456

THAT was the only problem I had also. THEN trying to put it back in correct position. My old body just does not want to manuever like that anymore

Where are you located? I have this problem in a 2006 911 c4s.

The accessible one thru the heater core. It will redirect/impede the AC cold air to reach the defrost vents at windshield level. For all of us living in hot very humid southern climates (specially TX, LA or FL) , that is the most important. The second one, (smaller and almost "unreachable" in 997s) are for front/vent redirection, but minimum inconvenience comparing with the "foggin-up" windshield that it solved with the big flap covered.

Quotes source post: 16993139

Moxie (SF) - Thanks so much for your post! I also have an 08 997 and trying to get this fixed. Maybe this is the wrong forum but your post and photos are the best I have seen for the 997. I fixed the first one through the heater core, lots of posts out there on how to do this one and pretty straight forward. In your photo you have the radio removed but it looks like you went in through the heater core opening to get to that second flap. Did you do everything through the heater core opening under the bonnet and did you need to remove the radio? Thanks again.

I'm in Santa Cruz, CA so anyone in the SF Bay Area or San Jose? Thanks!

Quotes source post: 18935038

I think you have that backwards. The smaller and almost "unreachable" one in the 997s directs the air to the windshield defroster. I did the repair on the easy to get one before I even knew about the second flap. Because I live in Florida, I immediately found out that did me no good as my windshield still immediately fog’s up. There is a reply above (#64) where someone went in through the heater core opening after removing the easy to get to flap and managed to re-cover this hard to get to flap. I’m thinking of going back in to try but there is almost no information about doing this second one on the 997’s. In Florida it’s a real problem with the windshield fogging up.

Quotes source post: 16444906

Unfortunately you only fixed 1/3 of the problem. It has to be removed to get to all the holes.

There are a few things that I would like to detail that may help others since I just finished this operation myself in my 2001 996. Re: the plastic pivots. They are slightly a "pressed fit" they wedge onto the metal flap. You will have to really grab and pull down on the bottom one. I used a small knife blade to pry it. Also the lower pivot can go in either way, the plastic bar cannot. On the top pivot; you really only need to cut the very top of the plastic cover off. The further down you go you will be cutting the plastic pivot bushing which you want to avoid. This bushing will need pryed up and out as well. Using the black putty stuff is a good idea to cover it up. No need to try and replace the cut off part. Re; the replacement foam. I would be cautious using HVAC tape made for a home. I have had the foil type come back off in 24 hours. For my procedure I used the tape made for tile called "musselbound" that **** is pretty much permanant. ALSO sand then clean the glue off with alcohol before retaping!!!

I just did this to mine this past weekend, except I accessed both flaps from behind the HVAC panel. Left the heater core in place. Of course I forgot to take a picture before I put it all together.

Thanks to all the excellent posts on repairing the old foam on the AC blend doors. I have a 2011 997.2 and just did this job including the second blend door. I wanted to offer a few tips I just learned to build on the excellent post from AMCPILOT. 1. As noted in prior threads, it is not possible to access the second AC blend door from behind the radio in a 997 (as AMCPILOT shows in his picture) - there is a bracket in the way 2. It is possible (as noted by AMCPILOT) to access the second door after removing the first blend door accessing from the frunk 3. However, it is VERY VERY difficult to remove the old foam and adhesive on the door, then position the new foam in place - the problem is getting your hands in there 4. As reference, I wear a size Small golf glove (Cadet) and I couldn't get my fingers on the entire door while the door was in any of the three positions 5. My wife has smaller hands and she could access the entire door - so I would recommend getting someone with very small hands to help with the job 6. One of those video probes was helpful to view back in the area but not absolutely necessary 7. I also ordered a hole plug set from eBay to just put caps in the holes but they didn't fit well enough to use (too small) 8. I used 1/8 inch Dynaliner foam (as opposed to Dynamat) as the replacement foam. I've had very good results with this stuff in the past. 9. Brake parts cleaner on a small cloth works well to wipe off all the gummy adhesive left on the door after removing the old foam 10. You can build some flexible angled attachments and duct tape them to your shop vac to clean out all the old foam pieces from the hard to reach areas 11. In order to place the new foam over the door, you can carefully cut out a template (using trial and error) that fits perfectly against the existing blend door to position the new foam perfectly before permanently pushing against the door 12. Then make some double-sided tape out of blue painter's tape to put on the template 13. Then place the Dynaliner foam piece (non sticky side) against the template 14. Practice putting this assembly in place a few times to get good at it - then pull off the protective backing and go in again, position perfectly and stick in on 15. You have to do this for both sides of the blend door 16. It will allow you to unstick it somewhat if you make a mistake, but once you push it on, it is stuck down pretty good 17. If you misplace it a little, you can cut the excess off the edge with a new sharp razor blade 18. Regarding the cap to cover the door hinge bushing that was cut off (as mentioned in prior threads), a 1/2 inch PVC pipe cap (non threaded) works well 19. For the cap, you have to cut a slot to allow for the heater core support to slide through and you have to wallow out the inside diameter of the cap somewhat so it slides on well 20. You can also drill a small hole in the side of the cap and self-thread a small wood screw through it. Then tighten this screw (just a little) to keep the cap secured 21. For overkill, you can paint the cap black and use some black caulk if you see any gaps - but avoid getting caulk inside the cap - only on the outside 22. To help reseal the foam panel flap that covers the heater core, you can scrape some of the tar-type backing off of some Dynamat and roll it into a thin line. Then add to the existing adhesive outline to get a better seal. 23. Note that these comments are in addition to ALL the other posts on this topic that tell you how to remove the heater core and perform the "through the frunk" method, etc. 24. Also note that my heater didn't work at first - I had to drive the car and get the coolant flowing well before it "burped" out the air that I had left in the heater core system. Then the heat started working as usual. 25. Final comment - this took a while to complete - having a helper with small hands and being patient and taking time to do the job right was the key for me - and it saved thousands of dollars! First off, thanks to AMCPILOT for posting this content, super helpful. I recently purchased a 997 and the very first thing I noticed was foam shooting out the vents and what I can only describe as sound like pennies jostling around in dashboard. I took the car to a shop and was quoted $7k to fix the foam issue. Eff that. I found this thread and was hopeful this was my issue, and got to work. Sure enough: Excellent... after a bit of dremel work, here I was: I was feeling pretty good until I read this entire thread and realized there is another flap that also might have issues that is not accessible without taking the entire dash out, or cutting up some the duct work from where the PCM lives, I thought maybe I could see if through the heater core opening and sure enough: It was almost bare. Shoot, so I found some videos and FAQS on how to cut the duct work to get to it, and took a look if that was an option on my 08 turbo cab, negative. I realized I could get my hands on that second flap, it wasn't comfortable, but I could do it, so I hooked up some jumper cables and moved the flap into it's three positions, great, I can totally get my hands on all parts of this flap. You can see it moved: Then I cut out some new new foam went in by feel only. I was able to totally re-foam this entire flap through the heater core cavity, I had to move the flap into the 3 positions so I could get it totally covered, it took a couple strips/passes per side, and it was a bit time consuming and slightly painful on the wrist, and I had to redo a couple of the attempts because I put it on crooked the first attempt, but all in all, it wasn't that bad. I was able to completely cover that flap all through that heater core opening without having to make any cuts, or remove anything other that the initial guide AMCPILOT provided. And the good news, no more penny sounds coming from the dash, no more foam, and now not only does the heat and cooling work much better, I can actually direct it as well. woot woot! $7k saved! Hopefully this is helpful for others looking to fix this issue[/QUOTE]

Quotes source post: 19071596

And completely off topic, you should replace your cabin air filter. They pull in and separate the pleats like that usually when they start to become clogged, and the HVAC fan starts to pull a vacuum on them. The filter is not flowing air like it should be. Well, that or it wasn't seated properly to begin with so it wasn't uniformly supported. / Pedantry off. Now back to our regularly scheduled program.

Quotes source post: 19071596

[Image-only post; no author-written text. Original image references:] https://cimg8.ibsrv.net/gimg/rennlist.com-vbulletin/246x205/carnies_2dbc1a2ebf3e5d839bd12ba327bfce5dc0cdfa60.jpg

Judging by the level of effort in all these posts, I think I'm just going to continue to pull the trapped foam out of the vents, and run the AC at all times to avoid the windows from fogging up for no reason. My AC runs poorly anyway, and I need to see if something is wrong with the compressor (makes an odd low audible pulsing whine). Could the lack of foam on the blend doors cause the AC to be rather worthless in 90f temps?

Thank you for the details for correcting the smaller blend door. Would you be able to provide the rough dimensions for the foam template (Step 11)?

Yes! The larger door blocks off the heater core or evaporator core or vice versa. When the foam falls off the air just goes through. Fixing the main hvac door is not that hard, I just did mine following a video on youtube QUOTE=Ben8jam;19072810]Judging by the level of effort in all these posts, I think I'm just going to continue to pull the trapped foam out of the vents, and run the AC at all times to avoid the windows from fogging up for no reason. My AC runs poorly anyway, and I need to see if something is wrong with the compressor (makes an odd low audible pulsing whine). Could the lack of foam on the blend doors cause the AC to be rather worthless in 90f temps?[/QUOTE]

Regarding the dimensions of the foam template, I wish I had taken a picture of the template. Using a combination of measurement and repetitive test fit, you can get it perfect using a little trial and error. From memory, it was about 7.5 inches tall and about 4.5 inches wide. Also, I cut 1x1 inch notches in the top and bottom corners of the vertical side that corresponds to the pivot point axis of the door. I did this in order to avoid any adhesive getting gummed up in the swivel hinges. Additionally, the outside edge of the door is wider by about 1/2 inch until you get about 1/3rd of the way up from the bottom. Then it cuts in by bout 1/2 inch and continues straight up to the top. This small cut in can be seen on one of the pix of ACMPILOT. You can also see it easily after you remove the first door. Also note that the first door is a little larger than the second door. And the first door effectively has two doors on different angles (as you can see from the pictures). One on each side of the pivot axis. The second door has only one door side flap that moves. When you cut the two foam pieces for the second door, keep in mind that they are mirror images of each other because they each stick on opposite faces of the door. If you make two identical foam pieces, one of them will be backward when you go to install it. The template works on both sides.

Quotes source post: 19076269

Here is a picture with the dimensions of the 2nd smaller blend door that I used based upon your suggestion of trial and error. Mine were close to what you suggested. I cut these templates from 1/8 Dynaliner. The picture of the templates was taken after I removed the foam from the backing. 997.2 C2S small blend door template - used to repair black foam issue

Quotes source post: 19072810

Do you have enough oil in the A/C system? Compressors hate being run dry, sometimes people recharge the refrigerant and forget that you have to put in a small amount of oil.

How much quieter is the HVAC system with foam on the entire surface vs. only-over-the-holes? Or with the ebay 3D-printed plugs, or some kind of high temp non foam tape? I'm finally getting ready to do this and am trying to figure out the benefit of cutting the foam tape so accurately.

Quotes source post: 19093274

I went through all the same thought process you mentioned before starting. I tried to figure out whether the HVAC system would be louder in some way if I used the plug kit from eBay or used metal AC tape instead of foam. I was wondering if the "noise" mentioned in blogs was (1) referring to AC duct parts tapping against each other because the original foam had been providing a dampening effect between the duct parts or (2) whether the "noise" was referring to a rushing or whistling sound past duct parts that previously had been foam-covered. There were no definitive blogs on noise except for one guy who used non-foam tape for the procedure and said he thought it might be noisier than before but no detail on what type of noise. In the beginning, I planned to use the eBay plug set for simplicity but the plugs were severely undersized and fell through the holes so I abandoned this pathway. I think the 3D printed plug you refer to covers the hinge bushing mechanism after the end has been cut off to remove the first door (if you were using the "through the frunk" method). I don't think the 3D printed plugs refer to individual plugs to cover the actual holes in the AC damper door (but I could be wrong). Regarding the noise, I started by really listening to the system before I began the procedure to get a baseline. My system had almost no foam loss on the AC doors when I began the procedure so the noise level would have been basically how it came from the factory. I used one continuous piece of 1/8 inch Dynaliner foam (as opposed to Dynamat) for each side of both doors (four sides in total for two doors). As you mentioned, using one piece of foam tape does require a good bit of patience to get cut and installed properly. All of the blogs give excellent instructions on the two possible methods to get to each of the two doors. For a 996 you can get to both doors using the "behind the radio" method and for a 997 you need to use the "through the frunk" method to access both doors. Regarding the noise, I am very happy with the sound after the fix. There is no rattling and the sound quality of the air flowing through the ducts is equal to or possibly quieter than before I started the repair procedure. Unfortunately I don't have a comparison of how it would have sounded by using the plugs or non-foam tape.

Quotes source post: 19002106

You were right. Got it reversed. Thanks for that clarification and with some hints from Moxie�s thread, finally did the job, including the second flap too. For 997 definitely the job need to be done from the frunk, across the heater core. For the second one (flap) I did what Moxie suggested, using HVAC aluminum tape and worked by �feeling� only, covering 2nd flap�s holes with several pieces of tape little by little. It took to me at least 2 hours to do that flap alone, and was uncomfortable and hard for my hand, but doable. Then the reassembly was easier and faster. For the big flap all is well documented and did no have any big issues. Just took my time. Now got excellent cold and heat AC (at request) and the most important (for my case at least) is that have again full control of vents flow so no more windshield fogging! I can get cold air full blast thru front vents only at wish. Seems the problem was finally solved. I took some pics of procedure, and planning to put some sort of instructions and hints when I get a little more time.

For those of you that have installed the aftermarket caps vs tape/foam does it matter which side of the blend doors the caps are installed on ? I bought 2 kits to be able to repair my Boxster and 996 . I don't think it would matter which side they are installed on but thought I would ask . I plan on using some kind of RTV or adhesive to hold the caps in place .

Quotes source post: 19094612

I did not use those caps. I used the tape and foam sheet glued on top as others did. For the 2nd flap just the metallic tape. For the pivot cap, I did no use the putty suggested, instead I found that a rubber cap was a more elegant solution. I affixed it with black tape.

Peripheral question but does turning the system off close the vents? I found an acorn inside the lighter socket yesterday and three more on the passenger seat. Weren�t there a few days ago. Where the heck are they getting in? I already built a fence around the cabin filter which kept them from camping out there but they�re still getting in somewhere.

Squirrels? Might try the bounce dryer sheets in the frunk, engine compartment and cabin. Seems to work with mouse deterrence.

Quotes source post: 19094735

thanks. I�m thinking mouse traps too.

Quotes source post: 19094926

I also stuff the exhaust tips and air intake with 0000 steel wool for winter storage.

Quotes source post: 19094676

Do you have an "After" pic with that rubber cap installed?

Quotes source post: 19095247

here you have:

Quotes source post: 19097638

Perfection. Thank you.

There�s a cutaway of a C4 996 at the Porsche Museum in Stuttgart. I was just there this week. Look at the condition of the foam�.

Quotes source post: 19128083

[Image-only post; no author-written text. Original image references:] https://imagizer.imageshack.com/img922/5272/CSTa0A.gif

Ha, it looks better than mine did when I finally decided to repair it.

Museum quality foam! Who knew.

Quotes source post: 19128555

[Image-only post; no author-written text. Original image references:] https://rennlist.com/forums/graemlins/roflmao.gif

I'm going after my foam (well, the flaps) in the next week or so.

I'm not sure what is worse here: that those flaps are made to disintegrate or that they are so horrendously placed in the car, so that it's absolutely painful to replace them. I'm getting more and more of these foam bits out of the vents recently, so I'll problable have to bite the problem and take care of it sooner than later. Makes me sick that apart from disassembling half of the interior, other methods are rather destructive. Terrible design.

I took my C2 for a ride today with temps in the low 40's. No problem with the heat after years of foam blowing out the vents. I'm going in next spring with the help I have received here.

Following these instructions but my aircon pipe runs over the top of the heat exchanger preventing me from removing the heat exchanger. Anyone else had this issue and know of a way around it other thatn degassing hte aircon and getting it ref illed?

That aircon line isn't run correctly. I would reclaim the refrigerant, relocate the line, and refill the refrigerant. But I can do all that myself, so I'm more inclined to do it. R134a is cheap here, under US$20 here in Texas.

Oh, maybe right hand drive is different. Maybe a Brit or fellow Aussie can chime in. That's definitely not correct for left hand drive.

Quotes source post: 19129067

I put off doing mine for several years. It's not THAT bad. Once you've done it you will ask yourself why you waited so long!

Quotes source post: 19137668

agree. Just take your time. Consider doing it during a weekend with spare time. If I have to do it now again it won�t take me half as long as the first time.

Quotes source post: 19137637

Looks like I have the same issue. 2007 RHD Cayman Really hope there is a way around this without messing with the AC system

Moxie - what car do you have? I have a 987.1 and am wondering if it is possible to get access to both flaps via the heater core. Has anyone with a 987.1 repaired both flaps using either method? The video of the behind the radio method is a 986 and it looks like they have more access because the dash vents come out with that center section. I a not sure the 987.1 provides that much access. I have a 2008 987.1 standard Boxster with lots of foam in the vents and the air controls don't work well. I suspect both flaps are totally foam free. Thanks.

Quotes source post: 19171458

I've done this on my 987.1 through the heater core; repaired both doors. The inner door required some interesting flexibility in the wrist, but it was do-able.

Thanks for the reply. That is awesome to hear. Did you use foam or aluminum tape? Any advice or pics to help get to that second door?

I am in the middle of this doing the heater core method. While putting things beck together, the round piece that secures the top of the blend door fell into the duct work. It’s the one we cut to get at. I can’t see where it went. Wherever it is, it’s not impeding any of the doors. I put my phone down there while recording and just can’t see where it went. I have a plan to secure the top of the blend door, but wondered if any one else did this and if they figured out where it went. thanks

https://www.amazon.com/Endoscope-Adjustable-Semi-Rigid-Waterproof-Inspection/dp/B0C4V5LWWL/ref=mp_s_a_1_3?crid=2AKWZ4DNKVSRI&keywords=android+endoscope+camera+with +light&qid=1704058318&sprefix=android+endis%2Caps%2C102&sr=8-3

Link to Amazon seems corrupt.

Works fine on my machine

Corrupt here. Just do a search for endoscope camera for iPhone or Android based on what phone you use. I bought thus one. Haven't used it yet. endoscope endoscope

Quotes source post: 19156156

The pipe needs to come off on RHD cars. (Have done it on my '98 Boxster. NZ car).

Quotes source post: 19197747

thanks mate. I�m assuming it�s as simple as taking it to an aircon place to degas the system, taking it home and removing the pipe to do the job, bolt it back up and then back to the aircon place to regas?

Quotes source post: 19215575

Yup. Beware the allen head bolts securing the pipe flanges can be very tight. Counter hold the flange to prevent the pipe twisting. Cover the open ends of the AC pipework with something like the cut off fingers of a nitrile glove to prevent dirt getting in. And get new o rings, there's one at each flange. Your AC shop may have, else need to look them up. The parts numbers are confusing, either 999 707 250 40 or 999 707 434 41. It's the green ones.

Hi. What foam tape do you use on these repairs. Width and Thickness and Manufacturer?

I did the repair of both doors through the heater core and I'm getting a weird thing happening. When I turn the car on and select, or have selected from the prior time the car was on, the middle vents, the air will flow through those vents for about 3-5min and then switch by itself to "leaking" from the top vents and barely come out from the middle vents. If I select the top vents, nothing happens, and if I select the floor vents, the air comes out of the floor and get very little leakage into the middle vents. I don't understand why the airflow works correctly the first few minutes and then I can't get any air from the middle vents. Did this happen to anyone else? Thanks!

After you replace the corrected flap, and before you replace the heating core and button everything up, connect your battery through jumper cables and cycle the air from low/cold to high/hot. Make sure your door flap is fully closed on low and fully open on high. I thought I put my retaining clips in perfectly, but in fact BOTH top and bottom were missing the connecting tabs. Note: I was also able to get to the second diverter (997.1), but only get my hand on half of it. The second one is NO easy task.

I�ve got the foam blowing out my vents on my 2004 996. Anyone in the San Antonio or Austin area that can fix or assist with the fix? Would appreciate the help.

Quotes source post: 19531353

Thank you for the reply. Yes, the second flap was super hard to reach. I probably did not do the best job on that one. I did check under the dash and saw that the vent stays open to let air into the middle vents for the first 2-5min but then it closes slowly and sends air to the windshield or the feet. It won't switch again with the a/c buttons until the car is turned off and on again. So I turned on the car and disconnected the connector to that flap motor and now the air is going to the middle vent all the time. Temporary fix until I figure out what is actually going on. I've had like this for a month or so and no other issues for now.

Look at this thread. https://rennlist.com/forums/996-foru...n-issue-2.html 4 years ago, user " AMCPILOT " was doing this in San Antonio for $75.

Oops, forgot to tag you. I posted a link to t thread for ya, sds911

Shoot I’d pay 375 to get my cars done in NYC it’s closer to $1000

I�m not sure if AMC pilot is still active. I sent him 2 private messages, with no response. Anyone else in the area of San Antonio or Austin that fixed the issue? Heck, Dallas or Houston too? I�d even go to Colorado🙂Feel free to send me a pm or reply here. Thanks!

325 posts I just read and no mention of the stuff used on the flexible closed cell foam cover over the mixing heater box. Or did I speed past it. I mean the tacky black stuff that keeps water runoff from the windshield from entering the cabin. It resembles windshield seal, that come in a 40 foot strip/roll. RTV is permanent -- cant' use that. I'm about to use Permatex Black Super weatherstrip adhesive 81850, but I think it may be permanent too. Help?

I purchased the part new from FCP Euro, it came with adhesive already applied- ready to go. I don�t recall it being terribly expensive. GL.

Dave: thanks for the info, and everyone else also. cost was $31.xx plus shipping.

So, can you at least reach both doors from the heater core box by manipulating the fan/temp so they move into a position where it�s easier? Or is there no way to do that without cutting the vent from the cabin? I�d rather not even do that and deal with the foam shooting out at my face until it�s all gone.

if you are applying the tape, you can reach but not very well. I was able to get a 2 or 3 fingers to place the tape down but i'm sure it didn't end up perfectly aligned like I did with the first door. You could check with a camera and keep trying until you get it pretty well.

I was thinking of getting those rubber caps and putting some sealant on them. That should be easier with 2-3 fingers by just feeling around for the right holes. That last part sounds dirty I know lol

I was able to reach both doors using wire tube brushes from Harbor Freight to clean out the old foam, and then used a remote grabber to place the HVAC tape on the doors. It�s doable -just time consuming.

Did you still have to cut the plastic hinge cap and remove one of the doors and all that? Trying to get out of that destruction.

I did, and it was not something I wanted to do either. It�s been almost a year ; the guilt is gone, and it�s amazing to have my AC back.

A mistake I made was I forgot to hook up the door arm linkage inside the car before buttoning up the heater core. It was grueling to get the door to drop in place. I almost had to tear the heater core out again.

Quotes source post: 19643440

haha the caps might be easier!

I plan to do the foam by the heater core soon. We just had our first cold / rainy day here in MN. My heater tends to work just fine, but I noticed today that when I put the car into defrost mode it only blew full heat. Will the heater core foam repair fix this or would this be a sign that I may also need to do the foam on the other blend door?

Quotes source post: 19724871

I think full heat is what is supposed to happen. if you are not seeing foam bits coming out of the vents I would not open it up. My 2001 TT has a center box and one on either end. The two ends are impossible to access withoubdash removal. A dealer will be expensive. There are Indy people who do this, but of course finding one near you is a matter of luck. The YouTube videos are frustrating because they leave out critical steps and are generally useless for sourcing materials. Good luck.

I just did the vent doors on my wife’s car. I am replacing the vinyl interior with leather so I had the dash out for that. Removal of the dash seems more daunting than it actually is the hardest part for me is removing the screws at the motion sensor in the center of the dash up by the windshield. I found it is easier to remove the turn signal/wiper and other lever assembly from the steering column than to try to maneuver the dash around them (it can be done). With the dash out removal of the HVAC box is not to difficult. Meir Schwartz has a very good write up on it with photos that was very helpful. You do have to evacuate the refrigerant as you have to break the system at the expansion valve in order to remove the airbox. I ended up removing the mount for the air bag sensor so I could get the support rod out of the air box just behind the lower portions of the center console. With the air box out of the car it is easy to reve the 14 screws and split the airbox. Then the doors can be easily removed, cleaned and it is easy to replace the foam. I did find that he recommended removing the main electrical cable that connects to the junction box on the inside of the firewall (it contains a number of fusible links) and the two nuts that hold the junction box on the firewall. I do not believe this needs to be disconnected in order to remove the airbox. I remounted it and fastened it in place prior to reinstalling the air box and had no issues with the reinstallation. For me the hardest part of the reinstall was getting the screw started on the back side of the air box the mounts the lower air guide tube for directing heat to the foot well. I bought a 2’ by 4.5’ sheet of adhesive backed 3/16” closed cell foam at a rubber and gasket vendor for $15. It will be enough to do all my cars and then some. I also bought some foam tape rolls 1/2” x 3/16” to replace the foam at the joints for the air tubes going out to the side vents, dash vent and lower vent tube. This was good practice as I have several (4) more 996s to do this same repair on and several friends who want to repair theirs. Let me k so if anyone has questions.

I ran a scope in through the driver side footwell vent, you can get a view of both doors and I think the condenser through there and its a pretty straight shot to at least get into the main duct area with the doors. The vent itself is pretty small, so tool access through it would not be great, but it might be viable to cut that out to give somewhat wider access. Would still need to fab something which can apply some kind of patch to the doors, but if its possible it seems attractive as there's nothing you have to remove first to access that vent. You have to set the hvac control to floor vent mode for it to open the access door and get in, those parts are solid plastic so it's tragic the actual blend doors themselves have these huge holes in them.

I am wondering if I could use some kind of mesh temporarily over the vents just to "catch" all the foam pieces and stop them from getting into my brown carpet and mats? I am not really bothered by any loss of heating or cooling capacity but the black foam leaves stains and spots on the brown interior... Any thoughts on that? Would some mesh and then full blast speed up blowing out all foam while catching it?

Quotes source post: 19868990

my foam has been blowing out for years

Quotes source post: 19869010

It doesnt bother me too much as I said issue is my brown interior and the black stains it leaves on eg the carpet...

Quotes source post: 19033806

I could use some help, thank you for the detail above. I hve removed the top pivot, and have removed the screw from the bottom pivot. But the blend door still does not come out. You mention you need to pull down on the bottom? What do you pull down on? I have an outer ring ampmd a small square inside the ring. Any help would be appreciated. Thanks.

^^^ I believe what others have done is to put the screw back into the lower pivot and pull down on the screw .

Thank you for the reply. what should pull down? Im i looking for the whole round outer assemble to pull down and out?

Started this project today and thought I'd add my two cents. Before pulling the flap out, I made a reference mark to be sure I put back in correctly: Before I put the foam tape on, I sanded the flap to give it a little more texture for the adhesive to grip onto. Additionally, I warmed up the flap with a heat gun to help the adhesive stick better. I found a $1.49 plastic cap plug at the local hardware store that had tension tangs on each side. After cutting and trimming one side down, it fit the cut top swivel area perfectly with strong enough tension that gluing it on wasn't needed. Next up is going into the center dash for the second flap.

Quotes source post: 19895343

Excellent tip with the cap replacement . How much of the original plastic did you remove in order to expose the pivot? I believe AMCPILOT said 4mm in his original post.

Quotes source post: 19896564

I cut it as close to the top as possible, maybe 1-2mm. It was so close I had to use a jewelers file to file down a little of the cap that was still intact.

FYI. My dealer only charged me one hour of labor and fixed this issue. How? I have no clue. I was told they had done it to countless other 996's. It was worth it to me not to struggle and potentially break something. I'm not the best DIY guy. It would have been an extra hour or two of labor charges to get all the foam out of the vents that was leftover. I just blasted the fan and it all came out. Now the HVAC system works perfectly.

Quotes source post: 19898321

Nice. Looks like they didn't charge you the book rate (hours)?

I had a local mechanic give me a quote yesterday for 4 hours ( $400.00 ) to do both doors . Says he does both through the frunk. He has done quite a few but has only done the repair with tape or foam . I purchased the VW plastic inserts and that's what I want to use . I may attempt myself .

Quotes source post: 19898321

What's the name of the dealer?

So today, I went into the center dash to fix the blend door. The only thing I did different from a lot of the earlier posts was using a box cutter to cut the housing. It's easy and makes a much nicer and cleaner cut than using an oscillating tool. Most the foam was gone and lodged into the vents, with both defroster vents loaded up with big bits of sticky foam. Such as mess.

I would caution against using the black Armaflex foam strip tape. I had some in the shed for a few years and the foam delaminated from the tape backing. The same thing may happen in your dash. This product is made by Armacell.

This one has been coming up a lot lately. I dropped the solution in a video. You Tube

Thanks a lot, Yogi. I'm sure you saw the foam on my dash at the Concours Saturday. I am planning on using the foil tape as well.

So I have a 2002 996TT that is shedding foam. I'm leaning toward the dashboard removal route assuming that with the dash out, access to the doors is much easier and there is no cutting of plastic parts? Another driver for the dash-out route is that I'm hoping I can address some of the interior rattles at the same time. Has anyone who has removed the dash found a way to mitigate the rattles?

My understanding is you run the risk of introducing more rattles if/when removing the dash. That said, I'll be removing the dash in my Targa in the next few months to make the fix. However, my motivation for doing so is primarily because I've been collecting parts to convert mine from partial leather to full leather. If I wasn't doing so I'd fix the foam issue without pulling the dash. I'd be lying if I said I wasn't nervous about introducing rattles, but I plan on going slow and methodically to lower the risk. Good luck!

What is the consensus on re-using the heater core cover/gasket? Do you need to buy some double sided tape or just re-use the old stuff still stuck to the cowl panel?

My old stuff sufficed.

Quotes source post: 19927724

Ok, thanks. The fewer parts I have to buy that start with the numbers 996 the better.

For those that only used the foil tape, have you noticed any annoying whistling sounds or degraded heating/cooling?

No additional or different noises with the foil tape method on the diverters.

I just got the VW plastic/rubber plugs that fit into all the holes in both blend doors to avoids any tape issues. Has anyone else gone that route? I plan to use the black RV sealant as �backup� glue to make sure they stay in place when I go through the dash and try it next week.

Quotes source post: 19935885

Thank you. I got the frunk side flap out and taped up and will try to add some to the inner one as I don't want to cut up the front vent scoop.

Pfbrooks do you have a part# for the VW plugs

Quotes source post: 19936591

This is what I ordered based on research I found from other 996 forums. Amazon Amazon

Quotes source post: 19941733

Did this work? Or have you not yet installed to confirm?

AMC Pilot, what material did you use for the foam/insulation to cover the flap itself and is there is a more specific name for the black dum-dum material that covers the flap pivot?

Quotes source post: 20283252

I made a video of my process: You Tube and used this stuff: Amazon Amazon admittedly the frunk technique is not a perfect solution (you can read the years of comments that help course correct), but there�s some decent procedural process views in the video that I hope help make people�s projects smoother and faster.

Quotes source post: 20284528

Well done and thank you for the excellent video.

why is the foam there in the first place? why are the holes there?

I finally got around to doing this repair after years of putting it off. I went through the center console and used a box cutter with a new, sharp blade installed. I only cut a flap on the flat surface of the plenum/duct (I did NOT extend the cut all the way to the top of the duct as many seem to do). For the repair, I used the 3D-printed inserts from DSP Auto which I had purchased on eBay a few years ago. I sealed them into place with the RTV that they recommend (Victor Reinz Reinzosil - anthracite color). The tape that I used was Nashua Dryer Vent Air Duct Tape which supposedly has a temperature rating of -40F to 212F. Fwiw, my two HVAC flaps had essentially zero foam left on them. I was actually relieved by this because it meant that the initial cleaning process would be much easier. After scraping off and vacuuming out all the foam that I could, I used 91% isopropyl alcohol and a sock to wipe down the flaps before proceeding with the plastic inserts and RTV.

Quotes source post: 20301981

So you used the inserts AND tape ? And you were able to place the inserts on both blend doors ? How did you hold onto the inserts as you lowered them and your hand/arm down into the cavity ?

Quotes source post: 20302812

No, I used the inserts on the blend doors and I used the tape to seal the center duct back up, the same as everyone else. Reaching both blend doors was relatively easy. My HVAC temp was set to LO and vent control was set to the Center vent. There might be some other configurations that work better but that�s what my car was set at when I disassembled everything. As to placing the inserts, I wore a nitrile glove to keep RTV from getting all over my skin. I simply applied a generous amount of RTV to the insert, held the insert by its outer perimeter, and then reached in to put it into place. It was somewhat messy but it worked and I made sure that there was no residual RTV on any of the doors� hinges or outer edges. After a few hours of drying time, I the hooked up the HVAC before putting everything back together. This allowed me to move both doors so that I could ensure that their movement was free. I do wish that the inserts were more of a snap fit so that I�m not totally relying on the lifespan of the RTV, but I suppose it will last at least as long as the foam (and probably much longer).

Quotes source post: 20303065

Appreciate the clarification . Thanks

I've been blowing foam for a while and had the telltale signs of a failed heater core (coolant smell, filmy residue on windshield)...so...time to tackle this one. Very much appreciate the extensive write ups and work of those who came before me. Huge help in getting this done. I studied everybody's process quite a bit before diving in and felt good about the probability of success. A couple of notes for those who come after me: (1) If you have a cabriolet with BOSE / MOST, you will need to remove the subwoofer from the passenger footwell. When I went to locate the lower pivot point, I was thinking to myself, "a lot of guys said this was tricky...but...it feels flat out impossible ". With the subwoofer in place, you can barely see the pivot screw let alone get anything on it to turn it. Take the subwoofer out and it's relatively straightforward. Taking the subwoofer out is easier said than done (and not a lot of online info about it). It is held in place with two H3 bolts - one is obvious up near the end of the footwell, the other is really hidden under the carpet of the center console: (2) I sort of suspected that my heater core was leaking (see above) ... but it was really leaking. The top 3rd was covered in pink coolant. I'm glad to have had a new heater core on-hand to drop into the box. (3) I was surprised at how intact the foam actually was on the door; most of the foam missing from the short part of the door came off as I tried to wrangle it out: If I had known how good the foam was, I might have just put the new heater core in and called it a day. Bad news on that is that the source of my cabin foam must be the second blend door (also because I can't get heat on my feet...)...so will tackle that next.

Given that there are 2 blend doors, does anyone know what each controls? Does going through the heater core and repairing the one solve all issues?

Quotes source post: 20327470

There are two issues and each is related to an individual door. If you have condensation inside the front windshield, you�ll need to fix one door. If you don�t get enough heat in the winter, you�ll need to fix the other door. If you have both issues, like I did, then you will need to fix both doors.

One door controls heat and cool, the other controls where the air flow goes between top vents, center vents and footwells

Great article thanks. As others have said the repair here is for the fresh air blender and there is a second one for which you either have to cut the duct work under the dash or completely remove the dash. However fixing the fresh air blender solves 80% of the problem. question for you - what is the name of the black �dum dum� material that you use??

Quotes source posts: 20327562, 20328360

Which door does what function?

Quotes source post: 20332349

The door that you get to through the heater core controls hot/cold; the door that you get to through the radio controls which vent it comes out.

It's duct seal - Amazon Amazon .

Quotes source post: 19137637

Just got the cowl off to discover the same issue on my .2 C2. looks like time to reassemle ...

RHD cars have the A/C pipe crossing the heater core like that.

Quotes source post: 20370840

doing some more searching it seems you can work around it so i'll try another day.

Old thread but man so well written by AMC I have no problem with the heat getting hot 120 degrees at the vents, but despite a correctly charged AC system with a brand new compressor that is engaging correctly, the vent temps aren't cold enough. I do see bits of foam exiting the vents from time to time. Worse lately, coinciding with the AC vents not blowing as cold Reasonable to assume the same door accessible near the heater core could theoretically not cause a problem with the heat. but could cause a noticeable difference on the AC temos at the vents? Assuming all was perfect with the AC system?

Quotes source post: 20432952

Before I fixed my blend doors (with aluminum tape) the temperature control did not make as much of a difference. It will get slightly colder or warmer but that was about it. After taping up the blend doors, I get proper heat and AC. With foam coming out of your vents, it's something that you have to fix sooner or later so it's a good first step in diagnosing your AC problems. It's pretty easy to do from the center console (but I have small hands which help when reaching in to tape up the blend doors).

Quotes source post: 20432960

Thanks man. And I believe its been said but to confirm that other door you cant get to from the top up by the heater core has nothing to do with temperature mixing at all right? Thats a deflector to send air down different paths to the vents?

Quotes source post: 20433054

I'm not sure if those deflectors do anything at all for mixing temperatures. I think its primary purpose is to divert the air to the appropriate vents based on your climate control selections.

Lastly I have read a lot about 'foam tape' . Does anyone have a specific thickness that they recommend / brand? Hesitant to just buy something no name from Amazon with poor adhesive that falls apart !

Quotes source post: 20433231

My experience was that until I pugged up (taped over) the diverters it was fogging up the front windscreen on those humid days. Once I tapped up I could then stop the AC air from bleeding onto the windscreen and reducing visability.

Quotes source post: 20432952

I've had this problem and fixed it on a 03 996 and a 06 Cayman. Both had almost no heat, but the A/C worked great! I think you need to have your A/C diagnosed/repaired.

Quotes source post: 20433279

I used these with a little sealant on each one to hold it in place and went in through the front to get both doors. Not too hard, just time consuming and it is a tight space to work in. Amazon Amazon

I did like shown in a number of video tutorials and used 3M aluminum foil tape like used on home HVAC systems. Works well. If you have some laying around, I would use it. It doesn't take very much of it. With that said, I just looked up the price for a roll of it on Amazon and the price is high! If you will never have any other need for this type of tape and thus the rest of the roll would go unused, the plugs SSDVC mentioned are probably the better value. With that said, I don't know what real-world disadvantage there would be to using quality plain 3M duct tape.

I used aluminum tape, on both sides.

FWIW. I'm a fan of using 3D printed plugs secured with sealant.

Quotes source post: 20434653

hello. What PCAR model did you use those plugs from amazon? When you say �you went to the front� do you mean installing it through the �Frunk�. Also may I know what sealant did you use? Thanks for your reply

Quotes source post: 16441365

(Why couldn't you use a couple of dots from a glue gun to hold the cap back in place?) MB

Hey guys, does anyone have a real picture of a Brand New original Porsche 996.2 vent door diverter flap? I would like to see if uguys can show me what a new one from Porsche looks like. There's so much confusion with this foam installation on the metal door, I would like to see an original Porsche one for myself. I can't find anything online. Thanks guys. MB.

Here are some thread posts on Rennlist that will give you a good idea of what the blend doors looked like when they had foam on them. Scroll down into the images for a bit and you will find good pictures. It was probably about 1/8" sheets of foam applied to both sides of the doors. https://rennlist.com/forums/996-foru...l#post16294489 https://rennlist.com/forums/996-foru...l#post16288892

I've always wondered why foam was used. My guess is that it's to diffuse the sound somehow.

Great thread. My �03 seems like it�s still functioning fairly well, but I did have a small piece of foam come out of one vent in the short time I've owned it so, I�m wondering what it would take, i.e., how involved it would be to disassemble the dash/HVAC & radio controls enough to access and remove the plenum? I�m thinking removal would allow for completely splitting the plenum to allow access to the mode/blend doors. I�ve seen folks remove the radio and cut an access hole in the plenum. This seems like it would be really difficult, especially with large hands. Seems like a knuckle buster for sure and also a bit slocky with the aluminum duct sealing tape closing the surgically modified plenum. I suppose a full-on replacement of the plenum is also an option, though I haven�t priced nor investigated. What are the thoughts of the group? Has anyone pulled the entire plenum?

Quotes source post: 20444436

The level of effort to remove the center console bits to get to the blend doors is about a 3 out 10. It's pretty easy. I removed both radio and HVAC controls. Once you cut the duct, it's relatively easy to get to the blend doors. If you have big hands, you can probably rig something up to stick the tape on all the blend doors. I would not replace the entire plenum (with an OEM unit that also has foam) when I can replace the disintegrating foam with aluminum tape for a few dollars (also, it is less disassembly and assembly to go through the duct and therefore, less chance for collateral damage- like plastic tabs breaking). Once fully assembled, you won't even know that you cut into the duct. Just my $.02.

Quotes source post: 20444436

There is a youtube video showing a tech removing the whole dash to access every part of the air-co ducting and do a complete job. Look it up for yourself. For me, no thanks. Not enough additional benefit for the huge added time and expense. A taped up plenum that works just as well as it did before the surgery doesn't bother me. Nobody is going to see it once the radio is reinstalled. If you don't want to go in through the radio access method, go through the frunk and heater core method. Additional things to break/screw up there plus you don't get access to three planes of vent diverters.

Quotes source post: 20444526

I'm with you bro. 26 year old plastics are brittle!

Thanks to @ flipnidaho and @ yvvvz for the replies. I agree it's probably way too much work just to split the plenum vs. cutting an access way into the front. I was simply curious if any on the list had gone that route. It just seemed to me to be a similar 'fix' to the blend door in under the heater core in the frunk, whereas the entire door/panel is removed making it easier to tape up or plug or what have you. I'm one of those over-thinkers who wants to avoid the quick fix...granted, there are times when the quick fix is best. Thanks again. Steve

Quotes source post: 20444118

Foam is two-fold: Keeps noise down, and most importantly, lets a little bit of air flow through, hence the name, blend doors. Btw, those plugs with sealant, I wouldn't do. The raised surface of the plugs will cause little vortex's, hence causing more noise. And the weight of them is a factor.

I pop riveted a .020 thick piece of aluminum on the door accessed thru the heater core opening to cover the slots.. I used epoxy adhesive to fasten plastic plugs to the door slots accesed thru the the duct behind the radio. Works perfectly. No tape that might come loose in the future.

Quotes source post: 20440480

Sorry, I meant to write that I went through the center console. I used some black RTV, nothing special. I did both my 2001 and my 2004.

Quotes source post: 20450259

I don't have any increased noise and my airflow in all positions is just fine. And, out of curiosity, how is weight a factor????

I was hoping to follow the method of accessing both doors via the frunk per the YouTube video below: You Tube In my case, the form was easy to remove, but the original foam backing was still adhered pretty strongly to the door. The air distribution door (upper, center and lower vents) was extremely hard to get to. I tried a number of tools, but was unable to reach some parts of the door. Since I figured that placing the plugs in this door was likely more difficult than removing the old foam/backing, I decided to give up on that door and access it from behind the radio as my next project. Removal/Repair/Reinstallation of the "Hot/Cold" door wasn't overly difficult. I ran into one issue that probably only affects 2% of the people that attempt this job. I was paranoid about cutting off too much of the airbox "tube" that houses the upper door plastic pivot bushing so I went minimal. Is it possible to not cut off enough to access the pivot bushing? Yes it is. After my cut I was left with a thin "skin" of the top cap. I used an exacto knife to cut this out, but I was left with a lip around the top that made removal of the bushing very difficult. So I'd advise 3mm as a target to avoid what I went through. Keep in mind that if you cut too much off, you'll be cutting the top bushing... Kudos to the YouTube poster who was able to fix both doors via the frunk, very creative approach.

I ended up accessing the Temperature Control Door via the Heater Core section of the airbox from the frunk and the Air Distribution Door behind the Center Stack (HVAC controls and radio). Others have accessed both doors from one or the other, but access to each door is easier if you do both. I've seen a lot of speculation on why Porsche used foam on both blend doors originally; I think one of the main drivers was to get a good seal between the doors and the airbox (to avoid "dilution" of hot air with cold and vice versa). With that, I put more effort into the Temperature Control door as I wasn't as concerned about having a little air coming out the center vents when I wanted upper or lower vents only. I was skeptical on some of the foam products that I've seen on various forums so I opted for a 1st layer of 3M VHB double-sided tape and a 2nd layer of foil HVAC tape, both wrapped around the corners to hopefully get the best seal possible. I removed the red VHB tape backing before adding the foil tape. For the Air Distribution Door, I went with the foil tape only. Even with the access door cut in the air duct, there is a deflector that makes access to the door difficult. I just made several attempts to get the tape to cover all the door holes. I was left with one small corner of the bottom hole open, but decided to call it good. There are several good YouTube videos and posts in this thread covering both methods (frunk and center stack); I'd recommend going through them as you can pick up some good tips for making the job easier. As a last step, I ran the fan at full speed in an attempt to get any residual foam in the system out. Some of it got trapped behind the vent slats so I used a 90 degree pick tool to break it up to blow it out. I did this for the windshield vents and the front dash vents. I'm happy with the final results, hoping that all the old foam is out of the system, but I'm sure I'll see a few remnants from time to time... 3M VHB 2-sided Tape-1 3m VHB 2-sided Tape-2 HVAC Foil Tape-1 HVAC Foil Tape-2 Temperature Control Door Reinstalled Center Air Duct Center Air Duct Access Door (Cut-out) Air Distribution Door Foil Tape Repair Center Air Duct Access Door Re-installed

Quotes source post: 19927712

I bet you can re-use it (like the door panel weather guards that go inside door panels that one can re-use seemingly hundreds of times provided you don't rip the material). another question: Can anyone confirm that the aftermarket plugs available on ebay today are the proper size to just pop in? I'm going to attempt this on my 996 gt2 but don't want to cut the duct on the inside. Rather, I'm going to try to access both doors form the frunk side and figure I might have better luck popping in appropriately sized plugs rather than attempting to place strong adhesive-backed tape while working blind and contorting my (large) hands in unnatural positions.

They don�t pop in per se as you�ll need an adhesive to permanently affix them. You can search my post history on this thread to see what I used. Whatever you choose, I recommend you use a product that is low VOC.

Thanks for the intel. Was hopping they would "snap" in securely, making it easy to get all the holes secure without using tape or adhesive.

I just got done doing this. I used the method in this post plus the method of putting plastic plugs in the vent selection door from the front in rchelicopterfun's YT video mentioned above. It took me several days working on and off because I made several rookie mistakes that made it harder and cost me time. Some tips: Make sure the pressure is released from the cooling system. I started my work about 3 hours after I drove it & forgot to loosen the coolant tank cap. I got about a half cup of coolant in my cowling area when I took the first hose off the heater core. To place the plug in the vent selection door from the front, I bought this set of magnetic tools. The black one worked pretty well but see below. Amazon Amazon Do NOT use round magnets! It allows the plug to pivot at the slightest contact with anything and you need to start over. Most of the magnets you see on Amazon are round so you have to look for the rectangular ones. I’d suggest 30 mm ones. Also glue one to the tool above. I bought my plugs from “cjmmotowerkz” on eBay. They print initials on the back of the plugs so I had to dremel them off to stick the magnets on. Not a deal breaker but kind of a pain. Until I re-watched @rchelicopterfun’s YT video, I didn’t realize the bottom hole in the vent selection door was slightly larger. I wasted a day trying to get one of the normal size plugs in there. The size is so close that it’s not obvious. If you decide to use foam on the hot/cold blend door, make sure it’s thin, 1/16” instead of 3/8" or something thicker. I bought the wrong type and it doesn’t allow the door to seat all the way. I ended up removing it and using HVAC tape instead. Make sure you mark the outside of the blend door control arm in the passenger footwell and take a picture. Also, the tab on the door has to be exactly centered in the hole or you won’t get the flange back on. I tried to hold in in place from the top by using needle nose channel locks but that put it off kilter enough so that I couldn’t get the flange on. For those of you with skinny arms who are wondering if you can reach the vent selection door from the front without using a magnetic tool, probably not. I’m 5’8” & 160 lbs. I was able to get my hand to where I could touch it and put pressure on the plugs with the back of my fingers but I didn’t have the room to manipulate anything with my hand. Have fun! Haha!

2008 Cab 6MT 109k miles Completed this over the past few days. Only had the confidence to tackle this due to the guidance from AMCPILOT, MOXIE and all of the other contributors to this thread. I used a 1/16� neoprene foam from Amazon, and then covered this on the heat/cool mix vent with some metal HVAC tape. Did the inner vent deflector from the Frunk (thanks Moxie) as I had installed PCCM+ and took great pains to bundle and pad all of the excess cables behind the head unit and really didn�t want to take all of that out. Plus, thought I saw a note that on the 997 there was a bracket in the way. Very difficult for me to cover the inner door. I have med-large hands. The inner vent deflector was completely devoid of foam and the vent position control was effectively useless - same amount of air came out each vent (defrost, center, footwell) no matter what setting it was on. After I got done, it works 95% good as new. I just don�t know how long the foam will stay adhered to the vent. I wasn�t able to press it on super firmly, nor tape it. I was able to able to foam both sides. I�m not sure if the original foam extended beyond the edges and I wasn�t able to. Other poster used different techniques (e.g the disks to fill the whole, or a single piece of foam). I bought a cheap borescope and couldn�t keep phase positioned well enough to leave it in place and have other hands available to application the foam. Really happy with results for spending such little $$, Hardly any air comes out of the vents not selected.

I had my Boxster at the shop for a few maintenance items . I asked the mechanic if he would install the 3D printed plugs if I brought them . He said sure . First time he has done the plugs , he usually does the tape job . He said it was a little trickier than the tape but believes it to be a better solution . I originally bought two sets so my 996 will be next . I was surprised when he said he did both doors via the duct behind the radio .

I've been following this "black foam" thread for 4-5 years, and interesting to read about the various solutions to recover the blend doors. The foam covers in my 2004 cab are long gone, presumably that's when the foam is no longer coming out of the vents. But what is the consequence of losing the foam, since I don't notice any effects? My 996 is in Florida year-round so is it a defroster or heat in the winter that becomes compromised? TY! /X3