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DWPC

Engine Failure Risk with 2002 or later

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New member here. If I get favorable answers to my question I may get to be an old member. I was ready to pull the trigger on a lovely '99 996, but reading more and more about their random and common engine disintegration, I've backed off. I'm not too keen on driving a car with Russian roulette in its genes. The decision would be so much easier to deal with if there were some odds or stats based on real data. So PCNA has kept the data secret so no one really knows the failure stats? Considering how many Porsches are owned by lawyers, that's surprising....but that's a different subject. I read one post by a (supposed) authority saying that 1 in 5 996 engines become toast and need replacement? That's an appalling number. Scandalous. But 1 in 1000 would be no less appalling for production automobile by a maker who promotes its excellence in engineering!

So my questions are:

  1. Is it true that the blown engine syndrome is a 3.4 issue?
  2. Are factory remanufactured engines immune to the random grenading?
  3. Are 2002 and later engines (3.6) immune?
  4. Is the IMS problem completely separate from the blown engine issue?
  5. Seems like the grenading is completely random and the owner can do nothing to prevent it. True?

I fell for Porsche hard about two minutes into a test drive. These cars are like automotive crack. I hope I can rekindle the ardor, but when I see so many stories about $12-15K engine bills, I think the constant worry will outweigh the fun. Maybe you can talk me down.

Edited by DWPC

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This isnt going to help...but kinda funny now that I read your post-

I bought a CPO 04 996 C4S Cabrio-6 spd 30k miles on it-locally owned-stored every winter at the dealer (great records of the car)-bought the car on Sat-blew the engine the next Friday (hole in the cam cover the size of a quarter)-and my wife was driving it...so no, it wasnt me having fun :)

New (rebuilt)3.6L installed-been beating the $#%^ out of it since and everything so far (2k miles) has been good.

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If you do search here you will find a plethora of information on this subject. Having personally experienced both sides of this issue I will try to answer your questions.

1. Random engine failures are an M96 issue. Not just 3.4's but 3.6 and 05' 3.8's as well (an the Boxster engines>) Porsche had a problem with the early 99's with porous engine cases. They replaced engines by the dozens in 99.

2. Reman engines are bettter than the originals. Porsche addressed the weaknesses (but not the design) but they are definetely NOT immune.

3. The 2002 to 2004 3.6 has random failures as well (still the same design.)

4. The IMS is usually the culprit but there are also issues with cracked heads/freeze plugs causing oil/coolant intermix (like mine did.)

5. The failures are random but there is some evidence that the cars that are drivin on a regular basis (and not babied) seem to have less issues. Some say the more frequent oil changes can lessen the chance of a failure.

I had a 99 that would have ran forever. Unfortunetly I crashed it with 77k on it so I didnt get the chance to see how long it would last.. I had a 2000 that cracked a head (pancake batter in the crankcase) with no warning with 68k miles. A member here just posted that he had just hit the 125k mile mark with the original 3.4 as the third owner with never an issue.

LN Engineering has a IMS retrofit that can give you some piece of mind. I would go to their website and see what Jake Raby has to say about the M96 engine. You may even want to give those guys a call. Bear in mind that they are in the business of rebuilding these engines so they may be a bit biased.

It's a hard call. If you are shopping for a Carrera look out for one with a reman already in it. I would pay more for a car with a dealer installed reman over the original engine.

Lastly look for one with a CPO warranty. I personally will never have another 911 without a warranty.

The 09 engines have a new design and have eliminated the intermediate shaft.

You are right these cars are very intoxicating. Just do your research and be patient.

I hope this helps. My facts may be off a bit but I did the best I could :rolleyes:

Good luck!

Edited by phillipj

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New member here. If I get favorable answers to my question I may get to be an old member. I was ready to pull the trigger on a lovely '99 996, but reading more and more about their random and common engine disintegration, I've backed off. I'm not too keen on driving a car with Russian roulette in its genes. The decision would be so much easier to deal with if there were some odds or stats based on real data. So PCNA has kept the data secret so no one really knows the failure stats? Considering how many Porsches are owned by lawyers, that's surprising....but that's a different subject. I read one post by a (supposed) authority saying that 1 in 5 996 engines become toast and need replacement? That's an appalling number. Scandalous. But 1 in 1000 would be no less appalling for production automobile by a maker who promotes its excellence in engineering!

So my questions are:

[*]Is it true that the blown engine syndrome is a 3.4 issue?

The 3.4 sees a lot (relatively speaking) of cracked cylinder heads, but both the 3.4 and 3.6 share

other failure mechanisms, one of which is IMS failures. Scuttlebutt is 3.6s are

better than the 3.4s but I don't know if there is data to back that up.

[*]Are factory remanufactured engines immune to the random grenading?

Maybe reduced if the IMS is better, but otherwise I wouldn't say immune.

[*]Are 2002 and later engines (3.6) immune?

No

[*]Is the IMS problem completely separate from the blown engine issue?

It is one of the mechanism of failure that 3rd party upgrades are trying to address

[*]Seems like the grenading is completely random and the owner can do nothing to prevent it. True?

For the most part yes -- but it depends on the cause. IMS upgrades exist, they have not

been around long enough to say they make it immune to IMS issues, but the basis

of the upgrade is sound.

I would also keep a good eye on the water pump and replace it either every 30k miles or

at any signs of seepage.

There are several third parties that are starting to do engine rebuilds and upgrade alternatives

to getting a engine straight from the factory.

You might be able to factor this worry in terms of upfront $$ and use it as a bargaining tool.

Mike

Edited by txhokie4life

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I have a 02 C4S with 92K on it and it runs like a scalded dog! No leaks of any type and no history of any major repairs, just all recommended maintenance performed on time or early. Like any machine, they can break but I personally don’t feel you should avoid a car you really seem to like if you do a thorough check of the car before buying.

One thing to remember with these forums is that no ones reports when the car is running perfect, it is mostly a compilation of problems. If you were to take any other car forum you will find similar threads on issues relating to that specific model. Granted, it appears to be a relatively high number of failures with IMS issues but to date I have no seen any official numbers. I suspect it is a small number.

Bottom line, do your homework, buy the most car you can afford and enjoy the hell out of it.

B)

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+1.. There you go someone with no issues. :D Like he said do your homework and be very selective. There are soooo many great 996's out there

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exactly. I have an 2003 C2 with 45K miles and not one issue as of yet. I drive it very hard every single day! I have no leaks or any issues. For the most part these cars are built like tanks. Like a German Panzer. If you have to worry about every little thing you will never enjoy the car. Should I drive it hard today or is something going to break? come on. Drive it hard and have fun. Life is too short to worry about the little things. If something happens with my car I will have to deal with it....but till then I am not going to sweat it and am going to drive it hard and do all the proper maintenance. I do know that people who have issues with these cars IN GENERAL leave them stored for winter and because of the long periods of sitting dry rot can take place causing RMS leaks. If you are going to leave it stored I recommend starting it and taking it for a drive every couple days or you might be asking for trouble. These cars like to be driven unlike some other exotics/supercars

I have a 02 C4S with 92K on it and it runs like a scalded dog! No leaks of any type and no history of any major repairs, just all recommended maintenance performed on time or early. Like any machine, they can break but I personally don’t feel you should avoid a car you really seem to like if you do a thorough check of the car before buying.

One thing to remember with these forums is that no ones reports when the car is running perfect, it is mostly a compilation of problems. If you were to take any other car forum you will find similar threads on issues relating to that specific model. Granted, it appears to be a relatively high number of failures with IMS issues but to date I have no seen any official numbers. I suspect it is a small number.

Bottom line, do your homework, buy the most car you can afford and enjoy the hell out of it.

B)

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There's one Boxster owner around Livermore, CA with well over 200K miles on his original engine. Regular maintenance and 5K mile oil change interval. He recently bought a used 996 Turbo to go with his Boxster which he regularly drives.

I've spent a lot of time talking to my local dealer's service writer and head mechanic. Some of the engines do randomly self destruct, but the vast majority don't. Regular maintenance and oil changes seem to be a common factor in improving your odds. 5-7.5K mile oil change intervals, instead of Porsche's 15-20K mile recommendation, is cheap insurance in my mind.

At the Ventura show in September, I talked to Charles Navarro (LN Engineering) for a while, and he indicated the 3.4 engines were the most reliable. Others have said the 3.4 engines aren't as reliable as others. There seems to be a lot more folklore than hard facts for most of what is being said online - the only common fact everyone seems to be able to agree on is that some engines go bad. If you read Porsche history, every model seems to have their share of issues. The newer models have the benefit of the Internet to expand your personal world of contacts to the whole world, so there are a lot more people you can directly contact to hear horror stories about failed engines.

I am assuming at some point, I will either: 1) need a new clutch, at which time I'll look seriously at the LN Engineering IMS bearing retrofit, probably a new RMS seal, and whatever else is reasonably doable when the transmission is already separated from the engine, or 2) my engine will fail due to nothing I could have prevented with regular maintenance. In either case, I'm expecting to have to spend some money to keep my Porsche sports cars running - that's just the nature of the beast.

Cars that are driven regularly, hard and often seem to have fewer problems, or so I've heard from multiple sources. With that in mind, driving and enjoying the car is much better than having a pristine garage queen. Chances are you'll be too scared to drive the garage queen out of fear of something catastrophic breaking, and something will break because the car has been sitting in the garage instead of being driven.

My advice to you is to find a car you like, have it thoroughly inspected, walk away from anything that shows any actual or potential problems (there are lots of used 996s and 997s out there, and they aren't getting any more expensive), and enjoy every day you drive the car. Be prepared for something horribly expensive to go wrong (nobody ever said anything on these cars isn't cheap, so don't buy one if you can't afford to keep it running), but don't let that stop you from enjoying it. And don't buy the car just for looks, as a fashion statement or to impress anyone; there are less expensive and worrisome ways to show off, car-wise. These are great driving cars, and that's what they are made for

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One more comment on experts - there are experts out there who have pulled many failed engines apart, identified 126 possible failure modes (or more), and come up with many replacement parts which are way better than the ones designed by Porsche's best accountants. I have no doubt that the engineering on these parts would make Dr. Porsche proud. However, these experts are also in the business of selling the parts they design, so don't go overboard with upgrading every conceivable engine part that might possibly go wrong. Given the price of labor, it might be more cost effective to just buy a newer car under warranty every few years. I realize you're looking at a 10 year old 996, so am assuming a new IMS-less 997 is not within your budget. Just trying to point out and put into perspective how easy it is getting spun up being overly concerned about everything that could possibly fail in these engines and trying to do something about it.

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I've had a 2000 C4 and now drive a 2004 C4S Tip Cab. Both cars were trouble free and virtually bullet proof.

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These forums provide a lot of subjective information and if you are looking for an objective evaluation on the reliability of the 996 pickup (Consumer Reports Use Car Guide 2009). You will notice that not all years of the 996 have the same reliability record. Some years perform better that other and model year 2004 performs very well per the consumer reports criteria. I would have never thought at looking at Consumers Report for Porches but since the data is available and objective it certainly is worth reviewing. You will be surprised that model year 2004 is a consumer report “recommended” year based on its reliability. We sit around these forums and read countless tales of blown engines and bullet proof engineering yet no one mentions objective criteria when evaluating a used car. The Consumer Report Guide at least can orient you towards some model years that are less prone to “failure”. I personally feel a lot of the problems with the 996 are user abuse and neglect (not driving the car). So much for my subjective views….Consumer Reports are by no means the only criteria you should use but finding sound advice on the “reliability” of a Porche is like finding a reliable garage queen in an old farm. Let us know when you find your queen. They’re out there……..

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well, I wouldn't say a lot of the problems with the 996 are user abuse. Since I've own mine I've been replacing components left and right. I've never worked on repairing a car so much in my entire life. Now, that said I enjoy the work. The Mods and people on this forum provide a wealth of information to perform just about any service. But in the end I wouldn't have expected so many components to go south. The service history on my car before I got it was extensive so it's been a constant repair since birth so to speak:)

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Did you ever consider looking at Consumer Reports to see if you were buying a good production year? Service records are good to have but tell us very little about how the car is driven. If your car had a long service history prior to purchase perhaps it might be worth looking to see how Consumer Report rated your model year. You will see that 996 had some rough years in terms of reliability. Not all production years had the same reliability numbers. Model years 03 and 04 were particularly good overall in terms of reliability. The earlier years 99-01 had more reported problems per Consumer Reports. Consumer Reports ratings are general classifications like “transmission, electrical, etc...." and therefore tell us very little about issues like RMS. It is not perfect but useful information to some consumers. User abuse is very subjective….

Jorge

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Truedelta has just released some new reliability ratings: Trudelta.org. They don't have enough data on 996s, but there are plenty of Boxsters in there, including a few owners claiming IMS failure, on cars as late as 2005. I think you might have to sign up to see the results.

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Here is my advice and I have nothing to back it up with so YMMV.

If I was going to by another 996 NA, I would try find one with a few miles on it, say 30K+. I would research that car to see if it has ever had an IMS or RMS leak, and if it so I would pass on to the next one. I think any given 996 is either going to be leak prone or it isn't and one's that had had one leak will likely have another. The leaks MAY be an indicator that a failure is in the engine's future. Like I said I have nothing but a hunch to base this on, but I learned a long time ago to heed my hunches.

Edited by deckman

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These forums provide a lot of subjective information and if you are looking for an objective evaluation on the reliability of the 996 pickup (Consumer Reports Use Car Guide 2009).

Since CR ratings are based on questionnaires sent only to CR subscribers; a pretty anal bunch to begin with, and not on neutral industry data, I don't give them much weight. Less than 5% of their subscribers bother to respond, and there's too much room for subjectivity in their questionnaire. I think CR's "survey" is useful to gauge QA trends in perhaps the top five selling names, not much more. The real sample of higher end makes; BMW, MB, Porsche, Jaguar, Audi, in their report is not very significant. I think if the basis of the annual CR survey was well known, far fewer would give it so much weight as a guide their car choice.

Edited by DWPC

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