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YOUR RESEARCHmore newbie questions
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Check visually or via engine serial number
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It must be checked visually or via engine serial number.
Leading evidence: 'Check visually or via engine serial number' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'last place i would ever look' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check visually or via engine serial number' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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I have monitored/maintained the fluid level in the reservoir, and have lubricated the frame joints regularly.
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One possible I found is this: 99, cab, 70ish K miles, 2 documented owners with replaced engine and updated IMS.
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I�ve replaced a few items on my cab, including rebuilt hydraulic rams, a rear window regulator, a broken hinge, and a new top (tops last 5-15 years).
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It�s pretty reliable, but some parts - such as the top fabric - are only meant to be replaced, not adjusted.
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Came here looking for advice on a cheap ebay 996, which I passed on. I'm still thinking about one. so I'm still here
Some questions I haven't found answered yet, and are a bit surprising to me, so if these are FAQd somewhere, please share:
Seems coupes are more desirable/valuable than convertibles, and I get it, same in the BMW world. But ae the convertible tops inherently unreliable?
I have read about IMS bearings and what failure can impact. Why do so many cars seem to have replacement engines, even without apparent IMS failure?
Many cars have rebuilt transmissions. Are certain years worse than others?
Are the C4S cars much less reliable than the C2, other than having 2 extra halfshafts to deal with?
Ok, I'll take a crack at this:
* I've had my 1999 Cabriolet since 2014 and have had very little, if any, trouble with the convertible top and/or mechanism. I have monitored/maintained the fluid level in the reservoir, and have lubricated the frame joints regularly. The top material itself has held up very nicely, including the plastic window which is still nice and clear after 21 years. I've cleaned both with mild soap and water during the regular car wash process, and the car is garaged so I'm sure that helps explain the top's condition.
* IMS failure is only one of several failure modes for the M96 engine. Others include D-chunk and cracked heads, and I suspect that early on in the life of these cars the replacement of the engine was the "go-to" solution, regardless of failure mode or severity thereof. It has become evident with the passage of time that an engine can be revived after one of these failures. My own car suffered a cracked head and I was able to repair and get it back on the road for approx.$1.5k.
* My car has a 6 speed manual transmission which has given me Zero trouble. I have proactively replaced the clutch, pressure plate and throw out bearing, as well as changing the transmission lubricant. I suspect the majority of the transmission problems with these cars are with the Tiptronic/automatic transmission.
* The C4 cars are more complex and heavier than the C2, attributable to the additional driveshaft and front differential, but equivalent in power so poorer in performance. I have read that the C4 only transfers about 15% f the power to the front wheels, which causes me to doubt if the extra weight/complexity are worth it. My own vehicle is a C2, perhaps C4 owners opinions will differ.
So there you have one individual's perspective, just remember, the cheapest 996 you buy will be the most expensive 996 you buy. If you want a good car, buy one from an enthusiast because his/her car will have been loved. E-bay is probably the last place I would ever look for a 996.
The weight difference between the c2 and c4 is equivalent to a tank of gas, and less than a passenger weighs, so unless you are tracking the car i dont think you will notice any performance difference with day to day street driving. Drive my 4s year round in all conditions, something i find to be a big big +.
Only get a cab if you want a cab. More moving parts, means more parts to fix if you have a problem. I�ve replaced a few items on my cab, including rebuilt hydraulic rams, a rear window regulator, a broken hinge, and a new top (tops last 5-15 years). The automatic folding top is a complex combination of motors, gears, pumps, rams, hinges. It�s pretty reliable, but some parts - such as the top fabric - are only meant to be replaced, not adjusted.
As for C4 vs C2, more parts again to break, but we�re only talking a 4 more parts - not much. And the C4 is supposedly just as fast around the track as a C2 because the AWD nature of the design was not for off-roading, but for performance around a track. I�m sure a top pro driver would be faster by a couple of seconds in a C2, but an average driver might be faster in a C4. I would make the decision on C4 vs C2 based on which car is nicer, better kept, etc. In other words, it doesn�t matter so much. Same with some cars that have LSD. It just isn�t a very big deal compared to other factors.
Replacement engines? The M96 engine has many possibly failure modes, including a dropped valve, cracked head, bore scoring, IMSB failure, etc. Replacement engines aren�t any better than a standard engine, unless it was rebuilt by FSI or equivalent builder that has addressed many of the weak points, including the IMS solution. Rebuilt transmissions? That�s likely due to how people may have driven these cars - too hard and too fast. Slamming into gears is not how this car wants to be shifted. People that know how to drive these cars probably will never have to worry about the transmission. Same with the clutch - should last 100,000 miles if driven properly.
Thanks. Here's what I find confusing, when I see an ad like this, and there are many like this:
So, IMS never failed, yet replacement engine, replacement transmission. Puzzling how that much can go wrong on what I've read described as "the honda civic of 911s".
Why was the engine replaced? That will tell you. If not IMSB, then cracked cylinder bore, or some other failure. Either way, if the engine indeed has the larger IMSB, then it�s probably a safe bet that the bearing will not fail. However, it is not safe to assume it has the larger bearing. It must be checked visually or via engine serial number. And the engine could still fail in a different way later on. These engines are not bulletproof.
Just putting the pieces together here from the Craigslist post and your thread, but if the mileage on that slick top 99C4 in the Bay Area doesn�t bug you, JUMP ON IT! That looks like a very well cared for example with lots of preventive done. That�s the kind of 996 you want. And it�s a SLICK TOP 🤪 super rare.
There are few cars that I like in cab form, the 911 just happens to be one of them. So far mine has been good the only issue and and an issue to look for when you are shopping is the rear window. On the earlier cabs the plastic window separates from the canvas. I knew that going in, I just haven't replaced my top yet since I was more concerned with getting it mechanically squared away. I have no real regrets not buying a coupe, for spirited driving and errands the cab is great.
Thanks. I'm taking my time, doing research. While I think the coupes will appreciate more, the cab makes sense to me.
One possible I found is this: 99, cab, 70ish K miles, 2 documented owners with replaced engine and updated IMS. It lacks PSM which is something I think I want, but otherwise might work.
Ive got a 99 cab and no PSM, and I don�t think I need it. Heck, I even turn off TC (traction control) on the track and in snow. My car is so planted, I never feel unsafe or scared to drive it quickly. But I also have pretty good (above average) car control skills. So I think it depends on what you want PSM for, and your skill level.
If my memory serves me correctly. PSM was not available on the 1999 996 with throttle cable, only traction control, and PSM was introduced with the electronic gas pedal (e-gas) cars. I have a 1999 996 Cab with throttle cable and Traction Control only. Love that car BTW, was driving it this morning and the muffler delete is music to my ears!
I agree. I don't have PSM and often push the car hard enough to reach the limits of my driving abilities - and it is probably still 30% away from PSM kicking in, even if I had it.
Good feedback, thanks. My car control skills are also above average, but with a 14 year old boy in the house, every safety measure helps
Woodman71, mind if I PM you with some local SF questions?
Is the 14-yr-old going to drive the car on occasion? If we are talking safety, a much newer car is going be several orders of magnitude more safe than a 996.
Well, not officially. But I've never forgotten the time I was 15 and I snuck out in my uncle's Mk1 Ford Escort GT and lost the tail coming around a corner (thankfully, I didn't hit anything).
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