33 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHGuessing from my last thread the 1999 Is a solid car
Reported or suspected cause
cam deviations were out of spec
Reported cause
No successful repair reported for this finding.
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Discussions that report identifying a cause
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Reported cause
or so, I got a CEL and it turned out that the cam deviations were out of spec.
Guessing from my last thread the 1999 Is a solid car
Read full discussion summary
Leading evidence: 'cam deviations were out of spec' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'cam deviations were out of spec' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check color of the coolant in the expansion tank' (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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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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1
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Reported cause
It was the intermix issue, motor oil and coolant mix from a cracked cylinder head.
Guessing from my last thread the 1999 Is a solid car
porsche had
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Reported cause
The issue was Porsche had to go back and use engine blocks that had previously failed quality control - and they tried to fix them.
Guessing from my last thread the 1999 Is a solid car
Install around 2001
Performed · outcome unconfirmed
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Performed · outcome unconfirmed
My '99 had an engine failure early in its life resulting in a later m96 engine being installed around 2001.
Guessing from my last thread the 1999 Is a solid car
Replace initial thought was "oh cool, the imsb
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Performed · outcome unconfirmed
My initial thought was "oh cool, the IMSB has been replaced twice" - it was a relatively high mileage car, so it seemed to make sense.
Guessing from my last thread the 1999 Is a solid car
Replace adopting new techniques, experimentation, pushing the envelop, adhering
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Suggestion
Yang is ever-changing, adopting new techniques, experimentation, pushing the envelop, adhering to new regulations, changing 80% of the parts every new generation, failing, making mistakes, fixing those mistakes the following year, making the car faster, stronger, better, more technologically advanced, safer, shaving weight because it�s too heavy now, cutting some corners because it costs too damn much now, and then trying to sell it to more and more people to make a profit based on the Yin reputation from prior.
Guessing from my last thread the 1999 Is a solid car
Replace imsb
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Suggestion
The previous owner then sourced a "used" engine (perhaps through the shop that did the previous work) and had them replace the IMSB before installing the engine (just to be safe).
Guessing from my last thread the 1999 Is a solid car
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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
33 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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My guess is that I was lucky. Nobody had a 1999 with a failed 1999. I�d really like to see some 1999 failure if possible.
Not to pick on it but to discuss the failure and then cure.
Half asleep when I wrote this sorry guys.
I am just looking for original 1999 Carrera�s that
have been removed kinky to see that looked okay which there were a few. Just anyone with the 99 motor that gave up the ghost.
I just worked on a 1999 with an IMSB that was just was wobbling and about to go boom. While doing the job, I noticed the AOS left a huge oil mess on both sides of the engine. The driver side plug O-rings also had failed and caused additional oil leak. If we wait long enough, I bet the Variocam soleloid, or its chain pads, or the entire actuator would probably fail.
So no, I would not conclude that the 1999 is a solid year.
I have a 99 and believe it�s a good year for a 996. Original IMS, RMS, AOS...
My tensioner pads need replacement at 64,000 miles, and I�ve had BOTH solenoids fail within 6 months.
And convertible top needs to be replaced again (someone did a top about 8 years ago).
Brian, what is the build date of your 99 cabriolet? Jake Raby says the earliest '99 represent some of the best 996 cars built. Apparently there was a factory fire that ushered it lesser quality engines after this point. Seems like I remember there being a cut off on the serial numbers if you care to do a little research on the topic.
However, it seems to me the car is still going to suffer from cylinder bore scoring due to all the elements starting with Lokasil bores. You have the 5-chain engine and so it tends to be subject to chain guild wear which means the guides and solenoids will have to be replacement once you start seeing an excess of 4 degrees of deviation between both banks of the engine. Intermix and d-chunk are also problems noted by Baz and experts on these engines.
I wouldn't live life in fear with these cars. Just go out and drive the thing. Keep a close eye on any weird noises or symptoms. For example, check the color of the coolant in the expansion tank. Is the color clear or is it cloudy like a milk shake. If you notice discoloration or oil puddles, then that's the time to drop the engine and have it repaired for intermix. Normally the cracks happen on the heads, but it can occur other places. That's just one thing you can do to help keep the fires small. If you ignore a problem, it will only get worse and expensive.
It seems he is trying to convince himself his car is special, and therefore not subject to the many known weaknesses of these engines.
May he enjoy his bliss (ignorance) as long as possible...
My '99 had an engine failure early in its life resulting in a later m96 engine being installed around 2001. Not sure of the failure, I just know it happened. My build date is 4/98. My replacement engine is now failing, though it runs and drives just fine with no hint of a problem. That is, until you change the oil and see gold flakes in the oil. Will be interesting to see what the failure ends up being, but I suspect it is related to failing fuel injectors and Jake seems to support that theory. He will be the one to tear it down this June, so I am excited to see what he finds. Hopefully I will be able to drive this thing for years to come after the FSI engine is installed.
Talk about irony. Jake once said on the forums that bore scoring and IMS bearing failure was similar in effect to a broken timing belt on the Japanese cars. You can take a proactive approach and replace it early, or you can wait until it snaps and replace the entire engine. A couple of people burned him using that analogy saying it wasn't a fair comparison. I thought it was a really good example. That night, I was driving home listening to talk radio and some guy called in and said he snapped a timing chain on his Honda while driving down the expressway. Ended up causing him to have to replace the entire engine. The timing belt service would have only cost him around $500 - $700 on those cars.
yep....I�ll never understand the hysteria over the M96 engine.
Every Porsche made after the onset of emissions control (I can�t speak to the early cars...never owned one) has had problems. People brag about the superiority of air cooled 911�s. Bull crap. I�ve owned over 10 in the last 20 years (and still own one now). Most air cooled 911�s need head work by 100k miles. Not long after that, many need full rebuilds. Ever priced an air cooled rebuild?
Does the M96/97 engine design problems? Damn right it does. However, after 20+ years these problems are known and ways to identify and proactively mitigate or even fix them are known. If you want to buy a 996/997 it�s no different than buying any other car...research the potential problems, have a good PPI and look for a good one. There is always a chance you�ll buy a bad one. But, we usually don�t hear from those who buy a good one. We hear from those who have a failure or get a �bargain� that turns out to not be such a bargain after all.
They should have stuck with the proven plan bearing design in the Mezgers and all the air cooled predecessors. If you want to have better understanding of why the bearing was changed, you should watch the IMS videos from PCA on YouTube.
I'm not sure what that means. I'd suggest STFU and enjoy your car. This incessant attempt to justify your position is getting old.
But this would require actual research.
Silver platter service to justify not spending money on preventative maintenance is so much easier than doing actual homework. Then he can afford more mods, spray paint, crayons and stickers to make his 99 even kewler!
C�mon man that�s not it at all. I�m concerned about my engine just like everyone else. Why can we just keep it cool. Of course I am hoping my engine doesnt break. But I admit right now it very well may.
I will look up my engine number today after
work. I�ll put it up here.
Where is it? I�ll do some google research as well.
right now he right great that�s all I can tell you.
Yeah, not sure why air-cooled comes out as superior or more desirable. They need head work and rebuilds as scheduled maintenance items. Not saying they aren't good cars, I've gotten to drive a few detailing clients of mine but they aren't bulletproof. I look at it like your car may be in good shape but plan for worst-case scenario.
Jake told me this story in 102 hands-on class and I took notes. I just looked back to see what I wrote. He told me that it's year 2000 cars to look out for, due to the fire. He said the telltale is a blue stripe on the engine block. The issue was Porsche had to go back and use engine blocks that had previously failed quality control - and they tried to fix them. The blue stripe is the old indicator that it had failed quality control. This is why those engines had unique issues to other M96's.
Also in my notes - if you guys think this is interesting - he told me if you see a magenta stripe on a M97 it means it's a rare M97 with a Mk2 M96 IMSB, not the larger M97 IMSB.
The reason: innovation
The casualty: mistakes
Using a yin and yang example:
Yin is stable, consistent, rule-abiding production of all the traits that make a 911 so great, unchanged, and if followed forever, would result in a disastrous car that is �perfect� for what it is, that a select few people would buy, but terrible by modern standard, resulting in Porsche going out of business. That�s a run-on sentence. So is the next one.
Yang is ever-changing, adopting new techniques, experimentation, pushing the envelop, adhering to new regulations, changing 80% of the parts every new generation, failing, making mistakes, fixing those mistakes the following year, making the car faster, stronger, better, more technologically advanced, safer, shaving weight because it�s too heavy now, cutting some corners because it costs too damn much now, and then trying to sell it to more and more people to make a profit based on the Yin reputation from prior.
Do either one to extreme and you die. Get the balance between the two wrong, and you might just barely survive. Strike a great balance between the two, and you excel. And it�s really, really hard.
I have a MY'99 that had at least 1 engine failure prior to my ownership. Upon my purchase it had 2 LNE IMSB Retrofit stickers in the doorjamb area (drivers side). My initial thought was "oh cool, the IMSB has been replaced twice" - it was a relatively high mileage car, so it seemed to make sense. Upon further resar.ch I found that the car has a replacement engine in it - an M96-04xxxxxx. Meaning that at least the original engine blew up - not sure why, but the fact that it had 2 LNE Retrofit stickers leads me to the following scenario: Original engine IMSB failure (perhaps stage 3 or 4) but not total engine destruction. Unscrupulous shop replaced bearing without pre-qualifying the engine (first IMSR sticker), and the engine self destructed sometime later. The previous owner then sourced a "used" engine (perhaps through the shop that did the previous work) and had them replace the IMSB before installing the engine (just to be safe). After driving the car for 10k mi. or so, I got a CEL and it turned out that the cam deviations were out of spec. I decided to do a bunch of work myself which included engine/tranny out - cam chains, tensioner pads, water pump, clutch, oil pump key, AOS, IMS Solution, etc. Overall, everything went well (besides overdoing the cam cover sealant a bit and having to re-do it). Unfortunately, after driving it for around a year and a half (about 10k miles) the slight ticking that it had always displayed when hot started to get worse. By this point, almost 4 years into ownership (and fearing what I now know) it became pretty clear I was developing a bore scoring issue. After all the work I had done (and the $ I had spent) in addition to my love for the car I decided that a FSI rebuild was in order. I couldn't be happier with the FSI engine. My point is, while the '99 my be a "great year" and generally better than some others, it's no "magic bullet". Do your diligence, and live with the outcome - it's a 20 year old car & there are no guarantees. Good luck
I bought a low mile '99 C2 Cabriolet just off lease. A couple of years later I had a catastrophic motor failure. It was the intermix issue, motor oil and coolant mix from a cracked cylinder head. This was somewhat of a common problem then and it happened to me. I worked hard with my local P dealer who I got to go to bat for me and ended up with a new factory reman motor goodwilled at no cost. I did pay for the R&R labor and fluids. Even though I do all my own work we bought a Boxster from the same dealership and I know several people that work there.
Downside with the 1999 is that:
- coolant expansion tank cost $600
- Chain guides are a PITA to replace (IMS guides requies splitting the engine, thousands of $$$)
Good thing with 1999:
- From what I recall less chance of D-chunk
- IMSB is apparently more robust
- No can bus so LS swap is easier
After reading 100000 posts about this it seems like frequent oil changes is the #1 factor of engine life (somehow this affect chain guide as well). And don't put on slicks and try to reach 2g for extended period of time with stock oil cooling system.
