Back in a 996 ? Took a Gamble on a 2005 C4S Cabrio

Just took delivery of a 2005 C4S Cabriolet and took an absolute gamble on this one. Bought it sight unseen and out of state. The car has a Carfax only a mother could love, but it presented surprisingly well in the pictures, had a decent amount of service history, and the price was hard to ignore, so I pulled the trigger. At $27,500, I believe it may have been one of the cheapest running/driving manual C4Ss in the country. I previously owned a 2002 C4S coupe, which I sold in 2018 and have regretted selling pretty much ever since. I�ve wanted another 996 for years and finally decided to dive back in before good C4Ss get completely out of reach. Anyway, enough rambling. Here�s the car: 2005 Carrera 4S Cabriolet 103k miles 6-speed manual White exterior � build sticker is unfortunately missing, but I believe it�s Carrera White Gray full-leather interior Wood interior trim Power/heated seats Not particularly heavily optioned from what I can tell The surprisingly good I�ve put about 50 miles on it since delivery and I�m honestly surprised by how well it drives. No smoke on startup, no obviously sooty tailpipes, no ticks or knocks, oil pressure and temperature stay right where they should, idle is smooth with no hunting, and the engine pulls hard and clean throughout the RPM range. No warning lights or obvious drivability issues. Clutch feels tight, suspension feels very composed with no squeaks or softness, and the underside is bone dry after driving�no leaks, drips or even much sweating that I�ve found yet. The convertible top initially wouldn�t open. Windows would drop and I could hear the latch motor running, but nothing else happened. Pulled the front latch assembly apart, manually released the stuck mechanism and got it working again. Top now operates normally. Interior also presents considerably better than I expected for a 21-year-old car with 103k miles. The bad The biggest mechanical issue so far is slow cranking, particularly when the car is hot. It turns over, but it sounds labored before firing. It has a brand-new Duralast Platinum AGM battery, but I measured only 12.33V cold. I�ve had it on a Battery Tender and the cranking improved as the battery charged, but there�s still some hesitation. Running voltage at the battery has been around 13.2�13.3V. I�m starting to suspect the infamous starter/alternator Y-cable, although I�ll do some voltage-drop testing before throwing parts at it. Tires are pretty much done, so those are getting replaced soon. Windshield has a chip. Front bumper appears to have been repainted and possibly the hood as well. Plenty of scratches/chips and normal cosmetic stuff to work through. The surprising As I started digging through the car, I discovered it has a Fabspeed carbon intake and Fabspeed exhaust, along with Bilstein B8 front struts that appear relatively fresh. There�s also an aftermarket Kicker amp/subwoofer setup in the frunk. So somebody clearly spent some money on the car at some point. I�m still figuring out exactly what�s been changed. One other interesting piece of history: the engine was replaced by Porsche New Orleans at 30,510 miles. I called the dealer and they were able to confirm the replacement, although they couldn�t pull up the original repair details anymore. That puts roughly 73k miles on the current engine. I�ve got plenty of baseline maintenance and inspection planned, including getting a look at the cylinders, oil/filter inspection, fluids, cooling system, figuring out exactly what�s on the suspension, and sorting the starting issue. For now, though, after the first 50 miles I�m pretty damn happy with the gamble. It�s definitely not a concours car and that�s exactly what I wanted�something I can drive, wrench on and improve without being afraid to put miles on it. Good to be back in a 996!

NIce looking car, sounds like you have a fun and fruitful project ahead of you.

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Great looking Cab. White/gray is very cool imo. Smart 💯

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yes, pretty excited to get into the guts and start upgrading where possible and getting some preventative maintenance out of the way! I don�t think I�ve seen this color combo in person before, it also has a blue top so nice contrast. Most of the white cabs I�ve seen have black or natural brown interior

Rarely see in white! Very good looking!

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yes, especially with the top down! White really accentuates the hips and rear end. snapped a quick interior shot:

Congrats and welcome back to the 996 club! Car looks great!

Color Looks exactly like my C2 Biarritz White 996, very nice looking 996, congrats...!!! Biarritz White (paint code L9A2 or biarritzwei�)

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Thank you! Yeah, that does look pretty close. Is there any way to determine the paint color outside of the frunk sticker?

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possibly from the vin #. Here is a pic of mine, what ya think, same color as yours..?

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Which frunk sticker is missing? My �99 C2 has 2 The paint color is listed on the build sticker underneath the hood. And it�s on a decal located on the driver�s side behind the trim panel. The one you pull back to remove the headlight.

Awesome! Good choice! White cars are faster than the others. Welcome back. Looks like an original non-put-upon owned car. Looking forward to the story!

It's a beauty! But in conflict with wikipedia: Only 4,012 units manufactured for 2005 model year. "Production July 17, 1997–2004 (2005 and 2006 for 911 Turbo S, GT2 and GT3 models only) " Care to share the VIN?

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looks pretty dang close! Nice c2! I believe the 996.2 all has a white build sticker underneath the hood, that�s where my last 996 had the build info Yes, definitely a car that was driven but also maintained over the years! Are you suggesting it�s not a 2005? They did build 996.2 Turbo and C4S in 2005.

Please provide the source of production of 2005 C4S models. I need it for my search, thanks!

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I�m not an authority, others can chime in. this Reddit thread has the info your look for: https://www.reddit.com/r/996/s/REszAls1Zi

Andrian Streather, Porsche 996 Essential Companion has alot of data. You can find it on Amazon. Here is a summary of production from the book.

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super helpful! Fairly small batch of c4s in 2005.

This is excellent! Wikipedia needs an edit! Only 763 of this model in 2005, very special car.

There was alot of 996.1 C2 Coupes sold, followed by 996.2 C4S Coupes. Not as many 996.2 C2 Coupes. This probably tracks well with why we see what we see on BAT for sale. Cabs and Turbo data is interesting as well. 996.1 C2 Coupes = 30,777 996.2 C2 Coupes = 12,666 996.2 C4S Coupes = 17,298

My 2003 Targa was getting really hard to start when the engine was hot, to the point it got pretty embarrassing to fill up at gas stations. Changing the crank position sensor did nothing but drain 3k from my wallet (long story). The battery was only three years old and still reading between 12v and 13v when driving, but I replaced it with a higher amperage one and that did the trick - the car starts right up now.

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All 996s came with the white build sticker under the hood. I�m guessing that yours is missing. Go through the first step of removing the driver�s headlight. Look behind the trim panel that you need to pull down to access the rubber plug. There�s a paint code sticker in that area. At least there�s one on the.1s.

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interesting, I just charged the battery and it now reads 12.6V, started it up and same issue. Wonder if the aftermarket sub, amp, head unit are causing some parasitic draw. Otherwise I�ll have to start inspecting the starter and y cable.

Congratulations! It looks like a pretty good candidate for long term ownership. 2005 with a replacement engine means it has the non-replaceable IMS bearing; apparently the thing to do is pull the plastic seal off the exposed side and let some oil get in there, and they last quite a long time. I suggest running a UOA on it right away to see what it shows. The aftermarket intake is sexy looking but it could be letting crud through.

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The engine was replaced in 2007, wasn�t aware of the non replaceable IMS. I personally am not concerned about the IMS, call me foolish. Yes planning to send off a sample to Blackstone after first oil change. Going to be using 5w40 liquimoly. With the fabspeed x pipe and intake I am kind of surprised how tame the exhaust note is. My previous 996 has PSE and it was much a deeper more aggressive tone.

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Dang, those are some of the wood items I�d like to add to mine (steering wheel, shifter, parking brake - swapped from original carbon). Looks great!

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looking at the chart again, just realized the staggering difference in production units for the c4s coupe vs cabriolet- ~11,500 more coupes�explains why I see far less cabrios for sale

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thank you very much 😁

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Fwiw, I would go with Driven DT40 or DI40 instead of LM. Those cylinders with last a long time if you run great oil and change it often.

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ok I already have the LM will switch over on the next interval. My wife grabbed a pic of the c4s in motion today, enjoying some brisk 95F Florida heat!

Replaced the engine lid hydraulic struts, the lid kept falling on my head simple 5 minute job

I saw this for sale recently and with the replacement engine, I thought that was very attractive too. Love the White with Blue top!

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Oh, any chance you may be able to see what part number is on the plugs in the circled sections? Mine are all missing and I�ve only had a hunch of what is supposed to be there.

@GTsilber Run the VIN through vinanalytics.com and you should get the build with exterior color

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Yeah looks great in person! yes can take a look tomorrow Thank you- it�s CARRARA WHITE (B9A) with graphite grey interior

First oil change complete � so far, so good Completed my first oil change on the C4S today using Liqui Moly 5W-40. Of course, nothing is ever completely straightforward on a 20+ year-old car. Discovered the existing oil drain plug was stripped, so that turned into a fun little project getting it out. Luckily, I already had an LN Engineering magnetic drain plug ready to go, so that went in as the replacement. Also replaced the oil filter with an OEM MAHLE filter. I cut the old filter open and went through the pleats pretty carefully. Happy to report no signs of plastic debris or metallic particles anywhere in the filter. I saved a sample of the old oil and will be sending it to Blackstone for analysis. Nothing about the drained oil looked particularly suspicious, but given that I have no idea what oil was previously used or how long it had been in there, I�m curious to see what the analysis shows. Took the car out for about a 20-mile drive afterward, got everything fully up to temperature and gave it some throttle. Oil pressure and temperature behaved exactly as expected and the car continues to drive flawlessly. So far, I�m really impressed with how this 103k-mile car is behaving. Next up on the baseline-maintenance list: Engine mounts Cabin air filter Spark plugs Coil packs Transmission mount Slowly working my way through the unknowns and establishing a maintenance baseline.

A very similar white with blue Cabrio 2005 C4S is on BaT right now. No Reserve: 2005 Porsche 911 Carrera 4S Cabriolet for sale on BaT Auctions - ending September 12 (Lot #262,900) | Bring a Trailer This one has a TIP

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Yep, very similar, minus the Tip and it�s a bit more miley. Curious to see how it ends!

Does anyone have some detailing tips to help remove prior attempts at paint correcting some dings. Paint color is way off and I�d like to touch up with OEM Porsche paint.

Slide under the left side rear and get the engine number off the block. It's above the sump, slightly forward on a Casting block. Take a rag and some cleaner with you. With that number we can find out what engine is in the car. Since it was replaced at the dealer, its likely an M96 "AT" or M97 engine. Both are later, better and will have the larger IMS, better casting and upgraded chain guides ect.. You might have hit the jackpot. My 2004 had the engine replaced by Porsche under warranty in 2006 and that's the engine I have.

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thanks! Confirmed it�s an m96 AT see pic

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This is a more common problem then you'd think. For this exact problem, what I've done successfully in the past, is use some lacquer thinner on a cotton swab. Let the soaked (but not dripping) swap sit on the bad touch up paint for a second then wipe it off. Might take a few times to get it all off. On bigger areas use a micro fiber with your finger doing the same procedure. The touch up paint is not factory baked on 2 part paint, so it should easily respond to lacquer thinner. Where the lacquer thinner should not damage the factory paint when doing this correctly like explained above... Or start sanding it off, then refinish the whole area... jmo

Thanks jmo will give that a try!

Couple of minor updates- changed cabin air filter and the sun visor inserts. The visor inserts were missing and I got them off alibaba for $9�hey it works! Simple stuff, next mission is fixing the hot start issue.

Dr. Color Chip for your replacement paint. DrColorChip.com

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You got a link for the sun visor inserts ? Was it whole assembly or just the cover ? I need at least 1 for my 996.2. And if they look as good as your pic, would change out both on my 996.1 that still works ok but the yellow sticker is in bad shape and difficult to remove so far...

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Here you go, it�s just the insert not assembly I just found this on AliExpress: https://a.aliexpress.com/_mtXbwUj

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Ty sir just ordered some!

New addition

Was feeling adventurous this evening 🤬 Plan was to replace the starter and y cable. I wasn�t able to finish the job. I did manage to break the intake manifold sleeve, the rubber just cracked and crumbled. So I have that part ordered. Also managed to drop the starter cable y nut into the engine bay and can�t find it. I also can�t break the alternator loose, tried the bolt trick still stuck. I also discovered that my car has an IPD plenum installed, was surprised by that. Decided to clean up the throttle body and plenum a bit. Now my car is in pieces, won�t be able to do much until parts come in. May replace the serpentine belt and idler pulley while their out.

I would get the other side boot too and 4 new clamps. If u ever pull the rear plenum replace the same parts too. For the alt just keep working at it but dont side load the bracket. It will snap....there is a member here that make a bilit replacent if needed. Check the part number on the tb its proably a 82mm gt3 unit ti fi with the idp. Go with metal pulleys if u replace any of them. A magnate with a flex shaft and head will be your friend for finding that starter nut. It would drive me nuts knowing its in there but it wont hurt anything.

Thanks @De Jeeper - I ordered the other side as well as clamps. The throttle body is actually the 74MM 997 Part Number, so its not the upgraded 82MM version..debating upgrading to the 82MM What other 'while your in there items' are worth tackling now that I have access to stuff (belt, idle rollers, engine mounts, etc?) You mentioned metal pulleys - is that the under drive from Tarrett? The missing nut is driving me crazy, I suspect once I pull the starter out I will have more room to look around and go magnet fishing!

No most of the replacement belt idler pulleys r plastic. If u keep looking u can find them in metal. The plastic pulleys dont hold up well over time. Dont change the crank pulley.

You�re close enough to consider Skip�s UAOS

Soaked the alternator bushing in PB let it sit for a few hours, still won�t budge. Have whacked the screw and bushing directly using ratchet extensions outside the car for max force�no luck.

Small kitchen torch on the aluminum. There is oxidation between the aluminum and steel sleeve. https://www.target.com/p/techef-buta...IaAj0tEALw_wcB

After more hours than I care to admit, was finally able to free up the alternator and remove it. Looks like this was already replaced as it has the 997 part number which is 150A. I wasn�t planning on replacing but I really don�t want to do this job again - think it makes sense to drop in a new one�thoughts? I will tackle the starter tomorrow, it�s practically out have one more nut to remove. as you can see from the pics, had to whack that sleeve a few times to move about 0.5mm then I started hitting the alternator housing to move the sleeve past the hole.

Starter is out, looks like this starter was replaced previously. The Y cable terminal connectors look corroded and the rubber boot seems to have melted onto the terminals. Will be replacing the starter and Y cable. Still can�t find that nut 🤷

Losing nuts on top of the engine is crazy. There are many nooks and crannies. I�ve needed a boroscope to go looking for nuts and bolts. Then a magnet on a stick to go get it.

Used my phone to take a video and saw it resting inside a nook on top of the engine block.

You may know this but the resonance flap inside the intake tube (circled) is a very common source of vacuum leak. I would suggest addressing it while you�re in there. LN makes a cap for it but I just bought a rubber vacuum cap at the local NAPA and use a worm gear clamp.

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Didnt know that! Will add that to the list.

Y cable looks completely fried

Some resistance there....causing heat. Thats why the wire cover is melted.

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Yup! Glad I went in there and removed everything. I will be replacing the Y cable, alternator and starter with OEM items. The alternator was ok but doing it for piece of mind. The old starter looks suspect to me, has the Bosch sticker but none of the components have the Bosch markings like my new starter.

Engine mounts done, old ones were shot. These look the original mounts.

@AeroF16 is this what you meant?

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Yes. To be honest, the clamp probably isn�t required but I was troubleshooting an idle issue I was having and I wasn�t taking any chances! The rubber vacuum cap was the perfect diameter, I think it was 7/8� (can�t remember) but it was too tall. There isn�t much room between those two cross over tubes and you cannot clock the most fwd tube much different because of the resonance flap actuator on the other side (towards the firewall). So, I used a razor blade and trimmed that cap down to size. LN sells a pretty looking machined one, I may do that when I got back in and install my UAOS.

Makes sense, I used a 3/4� cap�really had to maneuver it on there, probably should�ve gone with a 7/8� but I think this will work. I already prefitted the plenum to make sure there was enough clearance due to the cap height.

Lots of work in progress over the last week: 1. Starter, Alternator and Y cable have all been replaced and installed. No idea what the book time is for this job but holy cow it took a while�don�t even know if it fixed the slow start yet 😳. Added the 82mm throttle body. Getting that plenum back in was 🤦‍♂️ 2. Coolant cap replaced to .04 version ​​​​ 3. Started spark plug replacement�started because this is another case of why is this so difficult. Had to remove the muffler, which is standard procedure but even then, there�s practically zero space to operate. And my muffler bolts that were bolted to the mounting bracket were completely seized�that was fun 😁 Only managed to get the driver side off so far and worked on cylinder 3/2. The coils were cracked and the plugs had a bit of oil residue around the top. Will be replacing tubes all around with new coils and NGK iridium plugs. 4. Fister mufflers on the way, found a set for sale and will be installing those once the plugs are done ✅

Electrical engineer here. The melted covering on the Y cable was the proof that the cable connection was corroded and that was why the battery was not charging and then couldn't start the car. If the alternator had also been bad, it wouldn't have had enough juice to melt the cable. I think that half the time people complain that the battery is dead or won't start the car, the problem can be traced directly to a corroded Y cable as the source of the problem. It's a nuisance since we often end up needlessly replacing the battery or the alternator or both when the problem all along was a corroded Y cable. Note, no other car has this stupid swedged connection in the charging circuit. On the alternator, many of us are finding the rebuilt version sucks. I replaced my rebuilt one, which I originally installed because I didn't realize the Y cable was the real problem and the rebuilt alternator faded rapidly. I replaced it with a new Bosch and the voltage on the voltmeter on the dash shows just over 14 until all the fans are on then it drops to high 13. Voltmeter reading on the rebuilt was slightly lower.

You have the plastic pulleys. The metal ones suggested are from Murata or this one: Rauch & Spiegel Premium Billet Aluminum Drive Belt Pulley - Upper on Console. For Porsche� 986, 987, 996, 997. - LN Engineering The Rauch and Spiegel are a lot better. Here is a comparison of the plastic ones I took off my car after a year or two where you can see the spalling versus the metal one:

@996-CAB yes, I am relatively certain had I just replaced the Y cable I would be fine. But the starter didn�t look great to me and alternator appears to be the original. I did read lots of threads about new and reman Bosch parts that have been failing prematurely, was on the fence but bit the bullet. Would hate to have gone through all this work only to have starter crap out. Guess time will tell. Pulleys - yes, aware I have the plastic. I ordered what was described as metal Porsche pulleys (top, bottom, and tension) but what I received were plastic composite. I am doing the water pump and thermostat in a couple weeks and will source metal rollers for that job.

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OK, all good. I left the plastic ones on for two years. It isn't like they are going to break off. They just don't wear well. Before I knew enough about the Y cable, I took my car to a nationally known Indy (name I will not reveal because he was just ignorant and not stupid) and he tested the battery and alternator with a Snap-On diagnostic tool. Told me I needed to replace the battery (which was a year old) and alternator so I replaced them and the Y cable and just like magic I never had a problem and lots of voltage (at least until the reman alternator started to fade). But it turned out the real problem was the corroded Y cable. The Snap-On equipment and any of the standard electrical system testers cannot diagnose the issue because no other car has the stupid mechanical mating of wires left exposed to the elements! Here is what my Y cable looked like at the connection to the starter. Yours looked worse: The swedging of two cables was a cost saving measure: One cable instead of two and one connection to make instead of two. Bean counter caused failure point.

Ummm do I not have any spark plug tubes? What am I missing here�I thought they�d be visible 🤔

Nope. Yours is 2005, yes? Last spark plug tube was on a 2001 3.4L, I think...

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correct! Well that�s good to know haha�thank you!

Finally finished up the Fister install yesterday, got everything buttoned up, and was ready for the moment of truth�reconnecting the battery and firing it up. Then it dawned on me� I locked the frunk. With the battery disconnected. And just to make things better, my trickle charger was also locked inside the frunk. 😂 Had to rush-order a portable 12V jump pack, which thankfully saved the day. Used the emergency front hood release in the fuse panel, got the frunk open, reconnected the battery, and was finally ready to see whether two weekends of work had actually paid off. I�ll admit, I was pretty damn nervous turning the key. I had just replaced the starter, alternator, Y-cable, plugs, coil packs, engine mounts, and mufflers. That�s a lot of things to disturb at once and plenty of opportunities for something not to work. Turned the key, slight delay�and then I heard the starter engage. She immediately roared to life. And holy cow, what a difference. The Fisters give it a deeper growl and rumble that wasn�t there before, with a slightly throatier, more aggressive tone that reminds me of my old C4S with PSE. Exactly what I was hoping for. Took her out for a proper drive today, brought everything fully up to temperature, and made three stops along the way specifically to test the hot restarts. Every single time the engine cranked effortlessly and fired right up. Charging voltage is now right around 14V, so the starter/alternator/Y-cable work appears to have done exactly what I wanted. The engine mounts were another surprisingly big improvement. I had forgotten how much they affect the overall driving experience. Shifts feel noticeably tighter and smoother, there�s less slop and movement through the drivetrain, and everything just feels more connected and consistent. All told, I probably have 16�18 hours of garage time spread across two weekends into this round of maintenance, most of it lying on my back underneath the car. Absolutely worth it. Next round: water pump, low-temp thermostat, coolant hoses, pulleys/tensioner, serpentine belt and a complete coolant flush. Apparently I�ve decided that buying a 21-year-old Porsche means spending my weekends underneath it. 😂

Woohoo! Fantastic. Agreed. The moment of truth is always a touch unnerving. Congrats on fixes.