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THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHIMS Failure susceptibility across ALL 996 models?
Leading reported evidence
Replace but my engine failed
Performed · outcome unconfirmed
No successful repair reported for this finding.
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0
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Performed · outcome unconfirmed
My IMS,RMS and many other parts had been replaced but my engine failed for one(or several) of the other Modes of Failure.
Leading evidence: 'Replace but my engine failed' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'hoax have' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Recommend swap�' (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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Performed · outcome unconfirmed
Same IMS design has been used throughout the Mezger engines, it even has the old "959" part number on it where it was last updated...
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Suspected cause
People who think the IMSB problem is a hoax have to clue.....and they have never seen one of these below, the "non-existent IMS" from a Mezger..
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Suggestion
Imagine an Indy tells a customer the IMSB failure rate is very low and doesn�t recommend the swap� then a month later it fails.
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Suggestion
These cars are cheap to buy but expensive to repair/maintain.The repair/maintain guys are the ones to select with care.
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Suggestion
We supply IMS bearings to dozens of Porsche dealerships and in fact, dealerships were the first to use our IMS Retrofits because they saw the failures first hand and the need to replace the bearings.
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Suggestion
But it is real and if you are going to go to the trouble to take off the transmission to look for a leak, you may as well spend another grand to replace the IMS bearing.
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Suggestion
We supply IMS bearings to dozens of Porsche dealerships and in fact, dealerships were the first to use our IMS Retrofits because they saw the failures first hand and the need to replace the bearings.
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Suggestion · Original poster
I'm looking into purchasing a 996 4S, and the porsche mechanic the owner uses stated that the 4S cars have an upgraded part and they are not susceptible to the typical IMS failure associated with other 996's.
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60 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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Newbie here, (i've searched IMS failure) but I can't seem to find a definitive answer to the question of whether the IMS failure is limited to certain models of 996's or if its all of them (Carrera, 4S, Targe, Turbo etc..)
I'm looking into purchasing a 996 4S, and the porsche mechanic the owner uses stated that the 4S cars have an upgraded part and they are not susceptible to the typical IMS failure associated with other 996's.
I can find anything to support that information, so I'm tossing out there for any feedback I can find.
Thanks!
All except turbo and GT3 are affected - or, just in case that leaves something out, all models powered by the naturally-aspirated M96 motor, including the Carrera, Carrera 4, Carrera 4S, and the 986 Boxster.
On the plus side, it's not that expensive to address.
On the minus side, the mechanic is stupid, a liar, or maybe even a stupid liar.
It affects all 996's (even Boxsters) except turbos, GT2, GT3, etc since they use a different engine.
He's giving you BS, 4s is susceptible as well.
Now go back to read those 1520 threads on IMS
The 1999 996 has a dual row ims bearing as well as some of the 2000's ,
This bearing in the 99 has a 1%
Failure rate , bearings in later years have a 4.652% failure rate.
The good news is like 5CHN3LL said it can be addressed at not to much cost if its done before there is a problem. Be aware that MOST never have any problem without doing anything to them other than driving them. It depends on two things. One is your pursestrings and two is your personality. There are many cars for sale that already have the IMSB issue already dealt with if thats a big concern t you.
I would find another mechanic...and maybe another car if that mechanic has been working on it. Others have given you the failure rate skinny. I'm happy with my 03 C2 and unless you have a true need for the C4 you might consider good old fashioned two wheel drive. The cars are lighter and quicker and have more luggage space and with fewer moving parts will be less expensive to service.
If you haven't had you IMS fixed there will always be a small dark hole in your brain where you go to worry now and then. That is what I have chosen...no upgrade...its make driving more exciting than out of town sex.
I suggest that part of our response to noob IMS questions in future should mention the many other Modes of Failure to get a
competent
Indie to PPI/check.
My IMS,RMS and many other parts had been replaced but my engine failed for one(or several) of the other Modes of Failure. I mistakenly fixated on IMS & RMS because of all the IMS hoopla on the Internet.The failure was not major but the collateral damage was huge ! Total rebuild still underway as time and funds allow. Meanwhile no fun-car to drive and skeptical wife.
Also someone could crash into you and then maybe leave, maybe someone will steal it, maybe you'll lose it in a divorce, maybe you'll get drunk and forget where you left it, maybe you'll drive it two hundred thousand miles trouble free with the stock IMS and never even hear about the other failure modes. Maybe, maybe, maybe........
>>>I suggest that part of our response to noob IMS questions in future should mention the many other Modes of Failure
Absolutely. A tech bulletin, specific to the 996 shopper! Something like "it's a car. Expensive cars are more expensive to operate than less-expensive cars, and breakage is more expensive than maintenance. You should probably take measures to be informed and selective throughout the buying process".
Or just, y'know... "it's a car".
Great info everyone, thanks! Amazing feedback for a first post!
I plan on getting a full PPI from the local Porsche dealership regardless. I'm still in research mode and glad to learn all i can.
N
John, does anyone have a true need for any 911? I have had zero issues with the parts of my cars which are different from a C2. I would suggest that he buys whatever car appeals to him.
Conclusion: 1.) Get whatever 911 you want/can afford. 2.) Get a new (competent) mechanic at ALL cost!
TC
P.S.--Being an airline pilot, half of my sex is had out of town. I will quote BTO: "Any love is good love. So, I take what I can get...".
Scott,
IMHO - Forget the Porsche dealer. Instead, ask here on Rennlist for a few great, honest & competent Porsche Indies local to you.Vist them. take donuts,get to know them. Why? These cars are cheap to buy but expensive to repair/maintain.The repair/maintain guys are the ones to select with care. They may have a customer ready to sell and give you the whole back story. The dealer will give you ??????? there may be exceptions and for a CPO car O.K. but otherwise I doubt the Dealer will truly help you.
Here's one thing to learn - a Porsche dealer is not the best place to take a 996 for either a PPI or maintenance. A good indie mechanic is better. Dealers will be more expensive plus focus on the newer models.
I take mine to a Porsche dealer, I have the same mechanic all the time, who just see 996 and 997 only, I think that depends on the dealer, I like the warranty I got with every job performed plus keeping my Porsche book records, stamp and signed.
C'mon...
The 996 is now well over 10 years old (some pushing towards 20) so here are my two cents...
1) The few that actually had this problem have been either fixed or binned OR
2) The majority of 996's that have not suffered any IMS issues will most likely not have any such issues in the future.
I would not go out of my way to have it replaced until the clutch is on for a swap so let's stop this IMS hysteria...
PS. The percentage of 996's with a failure is nothing compared to most other makes/models out there. It's all in the car manufactures error rate calculation...
For our entertainment could you please contact this "Porsche mechanic" and ask him wtf a "996 4S" is and how the engine is different? Maybe he meant 996 C4S or 997 S? What a bonehead. Exactly why I cant stand dealers and wouldn't let them touch anything I owned.
So, for those who firmly believe that the earlier dual row IMS bearing does not fail, I once held in my hand the failing dual row IMS bearing I just removed from a early 996. It was a few hundred miles from blowing up the engine.
So did I , from a 1999 3.4 dual row with only 70K miles.......and I have pics/video to prove it......
People who think the IMSB problem is a hoax have to clue.....and they have never seen one of these below, the "non-existent IMS" from a Mezger..
Yes the Mezger has an IMS, but no one has ever heard of it because the failure rate is about 0.00034% ( Six Sigma) .
If you notice there is no roller bearing on either end of the Mezger IMS...Just two plain ole fashion babbit bearings..
Same IMS design has been used throughout the Mezger engines, it even has the old "959" part number on it where it was last updated...
No one is trying to sell you an IMSB you don't need,.. .
.There is another IMSB on the other end of the m96 IMS that is made into the oil pump front console that no one is trying to sell you either....why? because it WORKS....
The unheard of Mezger IMS that has a failure rate of about 0.00034% due to plain bearings ( no roller bearings)
No doubt that there have been isolated and rare cases of failure of abused and over-revved early 996s. Anyone can break anything. And there are experts with decades of experience like yourself who have seen this happen, almost once. I saw the green flash in Key West once and also saw an albino Narwhal in Seward. Just about the same odds as a 1999 dual row IMS failure.
No doubt that there have been isolated and rare cases of failure of abused and over-revved early 996s. Anyone can break anything. And there are experts with decades of experience like yourself who have seen this happen, almost once. I saw the green flash in Key West once and also saw an albino Narwhal in Seward. Just about the same odds as a 1999 dual row IMS failure.
Again� 8 yrs old. Also you might want to explain a Green Flash, you�d be surprised how many people don�t know what that is. I�ve seen two. One in the Med and the other in the Indian Ocean.
Lot of activity for a 'necro thread' I don't see the vitriol but there are a LOT of mechanics out there selling $5k IMS upgrades to 996 tip owners that don't need it. That's a real issue. Some of them even post here LOL
The belief that the Tip cars have lower failure rates is false. They appear to fail less often because they made a whole lot less Tip cars than manuals. If anything, Tip cars are more susceptible as they gravitate to top gear resulting in lower engine speed. Lower engine speed results in a slower IMS bearing race speed which shortens the life of the bearing. IE, you rarely see IMS issues on track cars because the average engine RPM is much higher - higher engine speeds increase the surface speeds in the bearing which is a good thing.
I don't sell IMS upgrades...but in fact I PAID the Porsche Dealer I retired from to replace the IMSB in my 1999 " Tip" Coupe last year......A young Tech, who I trained is now the Shop Forman there, did the work...
Yes. Our website doesn't currently have functionality to provide military discounts (it's in the works), but if you call in, this is something we do certainly offer.
Ha nice! When the sun falls behind the horizon, you�ll see a green flash if the meteorological conditions are perfect. It�s exaggerated in one of the Pirates of the Caribbean movie and I have close to 37 months of sea time and have only seen it twice.
Green Flash sold to one of the big boys a couple of years ago and is now brewed in Colorado I believe. Their old building is vacant and up for lease. We still have a 150+ breweries in the County though so I'm not too bummed.
As long as we are derailing this thread.... I still have a Farrah Fawcett pillow with the same picture as on your beer mug that was given to me in 1976 when I was recuperating from a bad dirt bike accident.
I think every kid that hit puberty in the late '70s had the poster or something else like your pillow.
"Boy oh boy, I am
so
mad at Farrah Fawcett-Majors. She is
so
conceited. She has
never
called me
once.
And after the
hours
I�ve spent holding up
her
poster with
one
hand! Geez!" -
Steve Martin, Saturday Day Night Live 1977
So first, the percentages people keepputming out are bogus. (MY unsolicited opinion) Just try and get your dealer to tell you how many they have done.. There will be crickets.
NOBODY knows how many IMS bearings have failed, the 1% and 4% numbers are from the investigation done during the lawsuit, about 20 years ago!!!
As the cars age the % WILL go up, maybe small amount maybe large. But most mechanical things the instances of failure go up with use.
Most of these cars are bing maintained at privateer shops, not dealers so Porsche has no idea, especially since LN probably sells more bearings than they do.
I also know of two dealers that sell the LN bearings when they need to do a replacement..
If you look at the whole motor, there are multiple wear items that likely won't be happy eventually,
and require splitting the case,, Chain guides, tensioners, cylinders, pistons, IMSB, Even a water pump can result in a Big Bang fail.
My car was blown by a failing AOS sucking oil in to 2 cylinders, hydro damage.. cracks then full rebuild required.
No PPI would have saved me. had fair records on the main items in the history of the car.
It was working, parked, ate breakfast, turned key on cranked it fired up and made a sound like a tiny ball peen hammer hitting an anvil 2wice.
The massive white smoke out off the right hand exhaust.
Cheers.
I don�t disagree but we live in weird times. Imagine an Indy tells a customer the IMSB failure rate is very low and doesn�t recommend the swap� then a month later it fails. I swapped mine because I needed a RMS and clutch, figured why not?
"While you are in there" is a pretty smart strategy with a 20+ year old car made of metal, rubber and plastic with parts that will eventually wear down and break from age, use or bad oil maintenence. Just the way it is.
I like the idea of being able to get into my 996 and drive from Chicago to phila and back w/o any worries. Same can be said for driving to the track, tracking it hard, driving it home and then taking my wife out to dinner.
Too many other things in life to worry about when it's pretty damn easy to keep your 996 in good working order.
I am a new 911 owner. A 2002 911 Carrera with 22,000 miles. It was literally a little old lady car, bought as a birthday gift on her 50th and driven on fridays. There is literally no visible wear and tear, no paint chips and it looks and drives like new.
I have been following the IMS bearing issue and was planning on replacing it until I met a fellow who used to work for a Porsche dealer as a service manager.He indicated that the issue is overblown and what they don't tell you at the Porsche dealer is that it basically only fails if you have an oil leak at the bearing. His comment was that if your car doesn't have an oil leak at the IMS bearing location then you won't have a problem. Wondering whether everyone's experience with IMS failures correlates with his comments.
Not sure why he would say that. There wouldn�t be an entire industry built up to solve a few of the well documented problems with the m96 engine. But it is real and if you are going to go to the trouble to take off the transmission to look for a leak, you may as well spend another grand to replace the IMS bearing. And get a new clutch while you are at it.
Being in Canada especially, I hope you had that engine bore scoped for cylinder bore scoring.
We supply IMS bearings to dozens of Porsche dealerships and in fact, dealerships were the first to use our IMS Retrofits because they saw the failures first hand and the need to replace the bearings. Just because the service manager at one dealership says something that doesn't make it so:
https://web.archive.org/web/20141221...ettlement.com/
Less than 1% "might" have been accurate 12 years ago...
Here's a 72k miles 2/98 build 996 that we started to do an elective job on last week... Also since all dual row cars are 5 chain motors let's add the cam chain tensioners from the same engine as well.
--Aaron
