Coolant Leak

First post, woohoo!! So I got my '01 996 in February of this year, has been a good car so far. When I got home from work today though, I noticed coolant dripping from the left rear, dripping onto the headers and then the ground. I popped the trunk and saw this... I took the air intake/snorkel off to see if I could see where the leak is, and its kinda hard to see but this is the best pic I could manage... The hose that wraps around and goes underneath the reservoir has coolant around it. The hose goes into an accordion looking rubber thing... Is coolant leaking around the reservoir a common issue for 996s? Does anyone have any ideas or thoughts? So whats perplexing is if its just a leak, I would see coolant on the ground, which happened. However, there shouldn't be any of that bubbling on the cap?? The first car I had was a z24 cavalier, and as I was driving one day my engine temp got pegged in the red. I got out and the coolant reservoir was super pressurized. What happened was the radiator just got plugged from really old coolant (probably never changed, and the car had like 130k miles on it). The coolant couldn't circulate, and it was bubbling from underneath the cap from all the pressure that got built up from the clogged pathway. Anyways, Im wondering if something like that could have happened? A hose or something is clogged, so the fluid bubbles out of the top and starts leaking around the reservoir on the bottom somewhere? I didnt notice the engine temp when driving home, but i have a short commute, fans didnt kick on and the enigne didn't feel any hotter than usual when I touch it.. Any help is appreciated..

You have the old style coolant cap and they are upgraded now for just this reason. Start by getting a new coolant cap that ends in 04. Take a hose and clean up the area with low pressure water. Check your coolant level in the tank and add 50/50 mix Porsche coolant and distilled water. Do not mix any other type of coolant in the expansion tank. If the coolant level is below MIN, raise the wire bail on the coolant valve so the system can burp. Then monitor it closely for a couple of drives.

Has the cap been off recently? Are you sure the cap isn't cross threaded? These tanks are old and known to start leaking. Edit, good eye. I didn't even look at the number..

Thanks, Im going to get some replacement coolant and the new cap. About the wire bail... I googled it and what I'm getting is- take ****ty cap off, clean off residue, fill reservoir with 50/50 mix coolant/water. Then I leave the cap off, right? Flip up the wire, turn car on, let idle for a few mins, rev a few times. Fill up the reservoir again, idle and rev. When the coolant level settles near max, place new cap on reservoir and flip wire down to original position. Clean up the area with water, and go for a short drive with fingers crossed. Here is my reference- https://www.pelicanparts.com/techart...lant_Flush.htm

Don't pay for pre-mix, mix your own! I'd take it for a short drive vs idling and revving. Take some coolant and a funnel with you so you can top off on the road if needed.

You can leave the bail wire in the up position for several hot/cold drive cycles. That really helps "burp" the air out of the system.

If you can,, Vacuum bleed it,,.. gets it done quick.. its worth it. that stuff around the cap looks like what I've seen when different types of coolant have been mixed.. If you dont know the exact history,, might be flush time.. Good luck!

He's got the common yellowing expansion tank. Time to replace that too!

So I got the 04 cap, replaced lost coolant, took it for a very short drive last night, everything looked fine, no leaks. I got to work this morning and same thing, puddling under drivers side exhaust. Going to order a new tank and replace that next, so I'll swap whatever fluid is in there. While I'm doing that, any common maintenance items I should check while I have the drivers side plumbed out? Also about the wire- do I leave it upright to burp or flip to the other side? I left it up, but when I opened the trunk after a short drive it was already flipped down to its original position so I'm not sure how much burping went down..

Lift straight . And get the genuine Porsche tank.

I would look further before just replacing the tank. Mine is doing the same thing. My Indy said the tank was failing and that was the cause of my leak. Replaced the tank, and on the way home it did the same thing. Back to the shop it went. It now looks to be a hose connection that is leaking, with coming off the backside of the heat shield and through the headers just like your picture shows. Probably two different spots on the ground as well? My tank was getting yellow, and probably would need to be replaced in the upcoming years. Just make sure to find the source of the leak before going out and replacing the tank. Kyle

So I've been reading for hours today and I'm starting to go down a rabbit hole of things to do.. Plan is to order new tank since mine is yellow and will probably fail soon anyway if its not the problem. Im going to flush the whole system to make sure I have clean fresh fluid, I'm not sure if the "lifetime" fluid was ever replaced or mixed with other coolant like pdxmotorhead said. Since I already bought the Porsche branded fluid I'll just stick with that.. While doing that I'm going to clean the radiators out since its a common issue as well. I have 2 ramps and 2 stands, so if I put the front on ramps, will I be able to take off the bumper? Or do I need to take wheels off the front to do that? I have MKI, so from what I've read I should be able to get away with that, MKII have a screw behind the small side lights thats only accessible from inside of wheel wells? I'm also investing in a uview fill tool I guess, and also an air compressor to run it. If I drain the old fluid, replace the tank, and hook up the uview, I can tell if I still have a leak if it doesn't hold vacuum? Or is that not a foolproof way of checking the rest of the system? Getting kind of nervous getting the rear in the air on jackstands from what I've read. My floor has a slight incline from a tree root uprooting it in the middle to make everything harder than it should be..

Mine is a Mk2, but it is a lot easier to remove the bumper cover with the front wheels off. It "can" be done with wheels on, but it's tighter. If you haven't come across it yet, Ahsai has come up with a simply brilliant way to drain the coolant that works a treat. Coolant drain Yes, once you have everything drained and hook up the vacuum filler, it should indicate that there are leaks as it won't hold vacuum. Not foolproof, but if it doesn't hold vacuum, it's got a clear issue. As for lifting, I think I would try lifting from the rear jack point. This will lift the entire side of the car. You can then place a jack stand under the front jack point and the ramp under the rear wheel. You then have the ability to remove front wheels to make the bumper cover job easier.

Most people need to take their car to a mechanic every year or two for a full vehicle check. A good tech will find most problems and those about to happen. Only a few have the 1. work area, 2. tools, 3. time, and 4. knowledge to fix their current issues and head off future ones. Any time I risk my life under thousands of pounds it is always supported by two points; so if not having a lift it takes 4 jacks and 4 jack stands to get a vehicle fully off the ground. In a different life I used up all my luck and so in addition to two points of support the ground must be level.

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I told you so! Watch Jake Raby's video on replacing the expansion tank. Very helpful in seeing the process unfold. Based on some other comments here on the forum, you definitely don't want to rush this job or you could easily break something and definitely purchase a genuine OEM Porsche tanks . And, on that note, you should order another coolant level sensor too.

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4 jacks?! Uh 1 jack and 4 jack stands work fine - and it's safe. Ramps work ok as well, but if your car is lowered at all, you probably won't be able to drive the front wheels on. I use lift bars if I need all 4 wheels off the ground - quick, safe and fairly easy...

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Yeah I hear you. When I get the car in the air I have 4 points and place the jack under the end thats on jackstands just to be on the safe side. The way my garage is, I'll put the car in backwards, so the ramps are under the front wheels and are on the side thats a little raised. The rear will be on the flat part of the floor on jackstands... I just hope I have enough room to back in and place the ramps under the front wheels, and not have the hood sticking out of my garage after I get on them so I can close the door. This is probably going to be a two day project for me this weekend.. I'll most likely take the front bumper off first thing, that way it makes loading onto the ramp easier clearance wise anyways. And after I got the car I took it to a local Porsche shop, did an oil change just to be on the safe side and had him "look it over." He said it looked good. No mention of any common problems, like the coolant tank or engine mounts. Kinda surprising, given they're always looking to drum up business. He did mention the IMS though, said I had a double row one so I shouldn't be as worried as the single rowers.

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And how does he know you have a dual row IMSB?

So I wanted to wrap this up, I've been driving for a month or so with the new reservoir and everything is looking good. My garage floor, you can see how bad it is On ramps, you can tell the passenger side is a bit higher Had the fronts on jack stands on the flat part of garage floor. Decided to clean out the radiators, check out the huge piece that was lodged in there. Passenger side, looks like they haven't been cleaned in a while. Same fluid, different color of bucket. I bought a quick fill tool, filled system with water, drained, filled with 50/50 mix. Reservoir cavity. Crack on the bottom, leaked out where the white spot is. Tight fit with that reservoir, ended up rubbing on the fuel line on the way out and putting those teeth marks on it. Seems like its just on the surface, I'll keep my eye on it. I was taking my time and being careful, dropped the engine a few inches, still had to fight it to get it out. I ended up cutting an inch of the top plastic support off to slide in the new one, still plenty of support IMO. TB was filthy, cleaned that out while I had the intake off. Some nuts and bolts around the intake had oil on them as well, like the one on the right. Kind of hard to see, but the left one is silver and clean, the right one is soiled with oil. Is this a sign of a bigger problem? Edit- pictures didnt attach for some reason... oh well