IMS Failure is not a Myth.

[Steve Tinker]

The TT (up to 2009), GT3 or GT2 Metzger engines are a different design to the humble M96/97 series - they don't have the IMS bearing but are much more expensive to manufacture....

[gregwils]

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

The scenario here is very similar to the old air-cooled days, hydraulic tensioners were failing and destroying SC motors. Porsche introduced pressure fed tensioners which did address the issue. The first thing people (should) check when buying an SC is whether or not the tensioners have been upgraded to pressure fed. Ironically, the cost to have it done is pretty close to an IMS upgrade. No one wants to spend the money, but if you look at as an insurance policy, it really is a wise investment. My $.02.

[NoGaBiker]

Originally Posted by gregwils

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

.

I suspect it's only catastrophic, not cataclysmic.

[mts]

Originally Posted by gregwils

There are really two issues here. First, the probability it will occur. Second, the consequence if it does. The first is highly debatable. The second is not - cataclysmic failure.

No one wants to spend the money, but if you look at as an insurance policy, it really is a wise investment. My $.02.

Good point. A big issue is if you happen to be someone in the 2%-20%, however you define the failure rate, you are looking at big $$ to get the car back on the road. As these cars get older, a good fix after a failure could in excess of what the car is worth. That is a terrible result.

My IMS did fail at around 20k miles. Porsche replaced the motor under goodwill, but since the new motor was unable to have the IMS upgraded at a reasonable cost each time I did the clutch (as recommended by LN with their bearing), I sold the car.

Whether 1%, 2% or 20%, the failure rate is unacceptably high, especially on low mileage cars and I can't think of another 1998-later car of any brand that has a catastrophic failure rate anywhere close to the M96 cars.

[Splitpin]

There are loads of brands that have issues, BMW diesels that ingest parts of the intake manifold, Minis that go up in smoke or just eat themselves as the timing chain tensioners fall apart, Ferraris have been catching fire also, alfas and landrovers having timing belt tensioner castings shear off. Porsche is not alone at all

[ohioboxster]

A little off topic, but the new Mustang transmissions are made in China and failing. For the last few years I've read so much about IMS, if I never hear those three letters again I'll be happy. They're the reason I sold my favorite car of all time. It was a 2002 Targa 911, what a car. I didn't know my TT wasn't in the IMS failure pool when I bought it. My plan was to just drive the car and enjoy it while keeping up on the oil changes and looking in on the filter.

[pothole]

Originally Posted by feelyx

I had done some research on the life span of the bearing Porsche used. According to a "person" in a bearing company that supplied Porsche with the IMS bearings, the 6204 has a limited life span. The bearing was shipped out with 1 seal missing and no lube in the bearing, so who knows what was used as lube, and who, what, or where... they used to snap on the other seal. Also, 1 more tidbit there is a percentage of lube used to the speed limit of the bearing. Example.. if the bearing has a limiting speed of 10,000 rpm, and you are running it at 7,500 rpm, then you fill the bearing between 33% to 50%. If you are running the bearing at 2,500 rpm, then you fill the bearing 50% to 66%.

Porsche should of left the bearing filling, and seal installation to the bearing to the mfg. and this would probably be a non issue. This research was done on the double row bearing used to '99, and if the bearing, was filled correctly, and not damaged on intallation, or overrev'd etc. should of lasted into 100k's with no problems. OH, and as soon as I mentioned "Porsche" the "person" shut up and would not give me anymore info.

Heh. Interesting story.

Personally (and I have absolutely no proof of this), but my view is there's way too much smoke around the IMS issue for it to be a minor flaw affecting a small number cars. All engine designs have minor flaws affecting a small number of engine.

You often read of Porsche employees not being allowed to talk about it. If it was a minor issue, there wouldn't be any need for secrecy because the potential liability would be small. On the other hand, if it's a major issue, the motivation to maintain strict discipline over who says what is critical.

But for me the most telling thing is that even if it's as low a, says, two per cent that's still very high statistically and certainly high enough that you would have expected Porsche to have rapidly addressed and to all intents and purposes solved the flaw.

When the problems with Nikasil liners became apparent in BMW engines in Europe, they changed the liner material. They also changed out bad engines under good will for getting on for 10 years.

I also wonder about the wisdom of messing with bearings that have proven longevity. Mine's on nearly 100,000 miles. Honestly, if you offered me a free upgrade, I'd have to think about it before taking it (well, assuming the fitter wasn't willing to replace the whole engine should the new bearing fail).

[thstone]

Originally Posted by pothole

I also wonder about the wisdom of messing with bearings that have proven longevity. Mine's on nearly 100,000 miles. Honestly, if you offered me a free upgrade, I'd have to think about it before taking it...

This echoes my thinking. When I had my clutch replaced at 92,000 miles, I didn't touch the IMSB.

[schnellman]

I had to laugh at the title of this post. Flat tires aren't a myth either, but I don't lay awake nights worrying about them.

[fivepointnine]

Originally Posted by Splitpin

There are loads of brands that have issues, BMW diesels that ingest parts of the intake manifold, Minis that go up in smoke or just eat themselves as the timing chain tensioners fall apart, Ferraris have been catching fire also, alfas and landrovers having timing belt tensioner castings shear off. Porsche is not alone at all

and 98-up Saab's with the 2.0/2.3 turbo that will randomly lose all oil pressure while driving down the highway, the E46 M3's with the crank bearings, etc

[nieuwhzn]

Originally Posted by fivepointnine

and 98-up Saab's with the 2.0/2.3 turbo that will randomly lose all oil pressure while driving down the highway, the E46 M3's with the crank bearings, etc

The Saab problem is because of sludge buildup. Change oil every 5000 miles and you're fine.
But yes, practically all cars have their little gremlins. The ones that don't usually get destroyed because their drivers fall asleep at the wheel

[fivepointnine]

Originally Posted by nieuwhzn

The Saab problem is because of sludge buildup. Change oil every 5000 miles and you're fine.
But yes, practically all cars have their little gremlins. The ones that don't usually get destroyed because their drivers fall asleep at the wheel

right but the sludge is caused by an inherent design flaw in the engine, just like the IMS.....I change the oil every 3500 with rotella on our Saab.

toyota's also have a sludge problem...

agreed most cars have gremlins that most normal consumers are just not aware of, I would venture to guess 70% of M96 owners don't even know what an IMS is.

[landrovered]

It is like having a history of heart disease in your family. It could kill you any minute and you can be proactive about it and do preventative diet and exercise and it can still kill you. Then there are those that have no idea they have a history and drink and smoke till they are 95 years old. It is a crap shoot. IMS is like that. I believe in being proactive but don't let the potential run or ruin everything in your life.

[Series9]

Here's the latest.


The engine went up to Flat 6 Innovations, where it was torn down. This bearing had been failing slowly and let debris into the engine.

This upped the total repair bill to $20k and the owner of the car called it quits.

Game over.

He told me today "The sad thing is that I know of two other (M96) cars sitting in garages with blown engines right now, and the owners don't know what to do with them. Mine makes number three, that I know of in this area."

[silver arrow]

Originally Posted by thstone

Well, no one thinks that the IMS failure is a myth. Its real and it happens. No doubt about it.

However, with over 200,000 Boxsters sold, if the failure rate is 5% or greater then there should be something like 10,000+ cars failed.

LN hasn't sold anywhere close to 10,000 replacement bearings. Sure, maybe some people part out the car rather than repair it but then you also have to take into account that some large percentage of LN bearing sales go to cars that have never had a bearing failure in the first place (preventative replacement). Other owners might find a salvage engine from a car that was totaled in an accident but there aren't 10,000 of those either. And last, if the numbers were that high then the aftermarket/eBay would also be flooded with failed engine Boxsters and we just don't see any of this happening.

The only conclusion is that the engine failure rate is much less then 5% (or failed Boxsters are with all of the socks that disappear from the dryer).

If I recall, LN estimated 20%+ failure rate. You aren't accounting for cars that got new engines through Porsche, rebuilt with the stock IMS (which was the only option before LN, and the cars that were just junked or parted out). At this point, many Boxsters aren't worth fixing if the engine fails. Sad, but true.

[feelyx]

Did you get any Pics of the bearing and seals?
Thanks

[fivepointnine]

Originally Posted by silver arrow

If I recall, LN estimated 20%+ failure rate. You aren't accounting for cars that got new engines through Porsche, rebuilt with the stock IMS (which was the only option before LN, and the cars that were just junked or parted out). At this point, many Boxsters aren't worth fixing if the engine fails. Sad, but true.

that would mean I would be seeing a Boxster on a tow-truck every day as many as there are around here! And there would not be any 100k+ Boxsters for sale on craigslist either (there are a ton)

I am straight up calling BS on 20%

[amschnellsten]

Here is the deal, it does and can happen but it is in limited numbers. This hysteria has killed the market. Last year a close friend of mine had purchased a 21k 2002 Boxster for $1600. The PO had the car from new and all of a sudden the oil pressure light came on at idle, the owner shut the car off and sent it to the Dealer. The Dealer could not find anything wrong but changed the oil pressure sensor and the oil light continued to light up. They told the owner that these cars have a high rate of IMS failures and that is probably what has happened and they would need a new engine. Needless to say the PO ditched the car and a my Friend picked the car up for pennies. He was planning on just swapping the motor out at his VW Audi tuning shop and resell it. He took it back and decided to dig into the car a little bit as he already had a motor on its way from a local yard. He found that some pressure relief spring had cracked, he went back to the dealer and purchased the spring for $7 his cost and installed it. Light was gone and the oil pressure was back up to spec. It makes ya think what hysteria can do.

[papasmurf]

these engines repaired/upgraded. I am sure LN, Flat Six Innovations and the like do excellent work, but the costs of their services and parts pretty much rules out the financial sense in repairing any 986 model boxster when the costs approach 20k...there just are not many/any 20k dollar 986's left out there.

Originally Posted by Series9

Here's the latest.


The engine went up to Flat 6 Innovations, where it was torn down. This bearing had been failing slowly and let debris into the engine.

This upped the total repair bill to $20k and the owner of the car called it quits.

[Saw76]

Originally Posted by thstone

As expected, each individual shop will see different numbers. Its the aggregate that makes up the big picture.

But please do not take my comments out of context. For the owners of cars with failed IMSB, the fact that it happens at all (and twice to one car) is obscene and Porsche really should do something about it.

And thanks for the pic's. Very informative.

Two in one car. I'm no mechanic just a weekend wrench guy with more experience in 914's than anything else and a new guy to the boxster world (2000 boxster 2.7 with 77,000 miles) is there any way this ins failure could have anything to do with a misalignment of the tranny to engine ? Causing unneeded stress on the bearing seals of cars ? Just wondering and just a thought.


Sent from my iPhone using Tapatalk