I have an '08 C 4S w/only 25,000 miles. Some of the forum comments are that mechanics want to steal your money, by changing out the IMS (by some methodology brought forward by a Texas Porsche racing mechanic).
Many guys say the iMS really isn't an issue, but since my last 997 ( an '06 w/ only 35,000 mi. was blowing blue smoke and had the engine changed under warranty), this makes me a little nervous since I don't have a warranty.
Any cause for concern?
Thanks!

 

IIRC your 08 engine is the last engine with the old style engine design with the IMS and its at risk IMSB ('B' stands for bearing).

While the last models are reported to be less prone to IMSB failure they still present some risk.

(In early 2009 I bought a new 2008 Cayman S as I felt the 2008 model engine was about as risk free as possible. Unfortunately an accident (not my fault!) just weeks after I bought this car destroyed the car and I do not know how the IMSB story would have turned out. But that I bought the car knowing all about this IMSB issue shows at least I was not that concerned. 'course, my experience with IMSB has been just fine. My 2002 Boxster engine and its original IMSB have been just fine now for almost 290K miles.)

Back to your car/engine: Again I have to add this qualifier: IIRC, but the later old style design engines may not have a field swappable IMSB. That is the bearing may not be able to be removed without splitting the cases.

Pelican Parts web site:

www.pelicanparts.com

I believe has some info on this -- look in the Porsche 986/996 tech article locations -- as does Jake Raby's company (Flat Six Innovations) web site:

http://flat6innovations.com

There are a number of aftermarket IMSB "upgrades" that provided your car's engine is capable of having this upgrade done without having to remove the engine and split the cases you need to research and consider if you want to go that route, of course.

 

Thanks that's helpful.
My mechanic does do those Jack Raby upgrades...
Others in the 997 forum have commented on how he just wants to steal my money...
My question is ...I wonder what percentage of 997's wind up with IMSB problems.
In speaking with my mechanic he seems to think they're all susceptible and likely to fail,
I would think that the Porsche factory would have addressed this after '06 or '07,
So that by the time the '08's came out this would have been rectified...

 

You will have to study the info at the links -- and any more links you can turn up -- to try to get a feel for the risk of an 08 having an IMSB failure.

I have not bothered to keep up, that is to try to keep up, with essentially the mythology surrounding the likelihood of such a failure. Some believe all engines are a minute away from grenading. Other people, not so much.

However, I believe your mechanic is on solid ground with the opinion they are all at risk of failure. I dare say any engine with the IMSB has some risk of failure. The trouble is knowing what the level of risk is.

You might be in kind of a spot, depending upon how much weight you put on the mythology. My impression is it is the low miles cars that appear to be most at risk of this type of failure. Your 08 is 7 years old and has averaged around 3500 miles/year. Porsche considers "average" miles for these cars somewhere between 6K and 9K miles per year, so your car is way under the low average.

Does this mean the fuse is burning on your car's IMSB? Well, yes, but with some qualification. Really, the fuse was lit the minute you drove the car off the lot but again we come back to the question of in this context how long is the fuse, how fast is it burning? No one knows.

There is too the question of what if any improvement the last examples of these engines have in this area. Again I have not bothered to research this. As I mentioned in a previous post I had enough faith (to be honest) that the 2008 engines were essentially about as low risk as they could be that in 2009 I sought out and bought a new 2008 Cayman S and I was quite wiling to take my chances that if the car made it out of warranty (on miles not time) that I would probably keep the car forever, and like it came from the factory, much like my 2002 Boxster.

Have to admit that I am not a fan of IMSB upgrades. They were not around when my 2002 Boxster came out of warranty. But the car had covered 50K miles and I decided that come better or worse I was going to hang on to the car, service it correctly, take care of properly, and of course continue to drive it and let the chips fall where they may.

But today if I were faced with a car such as your's I might be tempted to have the IMSB upgrade applied, provided it was doable without the extra cost of splitting the cases. The problem I have is I would not want an upgrade that was considered a wear item. Given my usage I could be facing doing one of these periodically.

To put this into perspective: I have put 290K miles on my 2002 Boxster since new. I put 140K miles on a 2002 VW Golf TDi bought a few months after the Boxster and sold in 2007. I put 40K miles on a 2006 GTO bought in 2007 and traded in in 2009. And I put 120K miles on a 2003 Turbo bought in 2009. I drive a lot. While 40K miles might seem like two car lifetimes to some folks, that can be a year's driving to me.

There is also something about this type of upgrade that just rubs me the wrong way. My general philosophy is if I feel a car/engine needs this level of aftermarket "help" it is a car I would just simply prefer to not own at all. I have not owned a lot of cars but those I have owned not one needed any aftermarket (or factory) upgrade of anything let along anything approaching the level of this IMSB thing.

Thus I would probably end up talking myself out of the upgrade. As an aside, even if one installs the IMSB upgrade, then while that I guess takes care of the IMSB failure mode, that just promotes the number 2 failure (whatever that is) to the number one spot.

So, I with a newer late model car with the IMSB I would probably just adapt the same mind set I had/have with the Boxster, and the Turbo (which is also out of warranty but of course free of any IMSB worry, but there are other things (the turbos for instance) that can be rather expensive to put right on the Turbo engine should they fail) and just drive the car and if the IMSB let go to try to have the presence of mind to recognize what was happening in time to shut off the engine and possibly keep the engine salvageable. Whether I would have the engine rebuilt or replaced or just sell the car and move on I can't say.

But do your reading, do your research and think about this. Talk it over with your tech. You need to make a decision that you are comfortable with. I can live with my decisions. But I wouldn't want to be so convincing that you had to live with them too.

I'm sure whatever you decide will be the right decision for you.

 

Thanks so much for the thorough response and taking the time to talk about this! You are a real gentleman in having spent the time on this comment.
You're quite right in that there's always something that's going to go wrong with a car and it's a roll of the dice to guess what that might be. And yup, there's always a number two waiting in the wings to surface after the number one is fixed.
They say that most of the Porsches that have been built are still on the road so that bodes well for the brand.
I'll probably put this off for a while anyway, and hope for the best and see how goes... Enjoy your ride...lots of wear and tear with those 40,000 miles a year!

 

The wear and tear ain't bad.

I mean there is servicing that is required. 5K mile oil/filter services. Rear tires every 20K miles, fronts every 40K miles. At some point spark plugs need doing. Transmission/diff fluid services are required. Brakes come in for servicing but brake life for me is so good I can't recall how often or at what miles these are done. I can look at the receipts I guess.

Then there are the little things. Besides the bigger things, to name a few: water pump, fuel pump; there have been door locks, window regulators, brake light switch and clutch/brake switch cruise control switches.

But people who see the Boxster and learn that it has big miles (now just 5 miles short of 300K miles) always comment on how good the car looks. And I'm not that driven to keep the car washed and waxed. I keep it reasonably clean but don't obsess over it. Sure, if one gets up close he can see the rock chips, a few small door dings from clumsy buttheads, some rock chips in the windshield, and most recently a faded spot on the top canvas that looks like someone used the wrong cleaner on the windshield and some got on the canvas.

But the car still runs/feels/drives and looks good. It is everything I expected a Porsche to be which is one reason I had no problem buying 2 more Porsches.

 

It's amazing that you keep your colors so long-- I think that's great!
If any car owner looks back at all their repair receipts over several years, there would have been always all kinds of stuff that needed to be fixed.
After all it's a machine.
It's all part of car ownership and of course if you have a new one with the warranty that's always great, but either way you pay for it whether you're opting for the high price of a car yet to depreciate, or one you own that's no longer under warranty, you have to pony up to play, and spend the time taking care of it. Somehow the fact that it's a Porsche, I seem to mind less looking after maintenance vs. other cars. Fact is, no matter what car you own, there'll always be maintenance issues.

 

I have a 2002 Porsche 996 with 27k miles I purchased back in Feb 2016.

The known oil change history based upon carfax and records I have show the following:

Date Mileage Service
9/26/02 10076 Oil & Filter Change - one year after purchase
5/4/05 14816 Oil & Filter Change
4/26/07 21411 Oil & Filter Change - 2nd owner
6/23/10 24324 Oil & Filter Change
3/6/13 25373 Oil & Filter Change
2/20/16 26522 Oil & Filter Change
3/4/16 26941 Oil & Filter Change
6/4/16 27231 Oil & Filter Change

Would this be considered adequate from risk of pending IMS failure for a low mileage car. The last 3 were done by myself after purchase as I wanted to monitor oil for any particles in my oil. The PPI mechanic found no evidence of metal or plastic in the oil in the 2/20/2016 oil change and I have found none in the subsequent oil changes I did myself

I also performed a Durametric Camshaft position check and the two readings held steady at 2.7 and 2.9 degrees respectively.


Thus I want to know if this car should be considered at high risk for a pending IMS failure given it has low mileage. The clutch is very strong and the engine has no signed of any fluid leaks. I plan on doing regular oil changes and inspections of filter and magnetic drain plug every 3 months


When I need a clutch or when I get to 40k I will do the clutch and IMS

Is that a safe approach?

 

It is an approach but how "safe" it is I can't say.

That the oil filter is free of scary debris and the cam timing is apparently ok is all well and good but IMSB's have a habit of going from just fine to in bits and pieces in a short time and one maybe gets just a few seconds warning if that much. If the IMSB starts to make noise because it is this >< close to going out before you decide the noise is worthy of shutting off the engine and having the car flat bedded in the bearing state could deteriorate and there you go.

I'm no expert but I have to point out "low miles" cars appear to fall prey/victim to a failed IMSB more often than high miles cars.

But there are I dare say many more "low miles" cars than high miles cars. So maybe (maybe) the two basic types of cars and their failure rates are about equal?

Or maybe not. Ok you have a low miles car and one that is (possibly) at a higher risk of suffering an IMSB failure.

If you are concerned about an IMSB failure and I think it safe to say there is a risk but how much of one I can't say (don't know to be honest though I wish I did to share it with you and every other owner who faces this possible situation) you need to decide if you can live with the risk or if not then have something done to hopefully prevent something bad from happening.

You of course then have to decide what something to have done, which flavor of IMSB upgrade to go with if that is the path you decide to take.

If you are concerned I would probably advise you to *not* wait until 40K miles. A lot can happen in the 13K miles remaining before the car reaches that 40K mile mark.

And I have to kind of laugh (not at you) but at the idea (and I know you did not come up with this idea for I've seen it offered before long before you offered it) of waiting until the clutch needs doing. My 2002 Boxster is on its original clutch and now has over 303K miles on it. Obviously in some cases one can be waiting a long time before the clutch needs doing. In the meantime this obviously gives plenty of time for something to go wrong with the IMSB.

So, it seems to me if you are concerned about the IMSB and believe you need to do something preventative in nature to do that something "now".

If when doing the IMSB upgrade if that is what you decide upon after consulting with your trusted tech and your trusted tech believes the clutch hardware, the RMS, whatever needs replacing then replace those things at the same time.

 

To follow-up on your response

I am aware of the low mileage car issue and Im someone whom had changed only one clutch in 4 manual transmission cars I have ever owned.

Looking at cars.com

I see that 30 out of 485 Porsche 996s (1999 to 2004) model year listed for sale have an IMS upgrade. For model year 2002 6 out of 84 listed for sale had an IMS upgrade. This amounts to 6.2% of all 996s and 7.1% of all 2002 996s for sale. Just FYI: A sample size of 383 vehicles is all that is required to represent a total population of 200000 Porsche 996s sold with a 95% confidence level. My sample size is 485.

This statistics could be interpreted 3 ways

1) The percentage of all 996s that have been upgraded. This would imply that there is not too much concern about the issue or maybe a lack of knowledge about the issue.
2) The percentage of vehicles for sale on the market with an IMS upgrade, a higher number of vehicles being upgraded are being held longer so not on the market. That is owners hang on to the IMSB upgraded vehicles longer. However in my search for vehicles I found a few recently upgraded which may indicate a lack of confidence in the upgrade and a desire to sell on a perception of how good the upgrade is perceived.

3) The statistics used to support the % of actual IMS failures could be based on the number of IMSB bearings replaced / total number of 996s sold. The 6 to 7% number of vehicles with IMS upgraded is close to the reported 8% failure rate of the bearing on the internet boards.

When I spoke to 4 separate shops about doing an IMSB bearing 3 of those shops said that they rarely see a vehicle with an actual failure in the past 10 years. The ones they presume were failures were the rare vehicle that showed up with a blown engine. These shops have all replaced IMSB before but all said they never took out a bad OEM bearing when they replaced it with an upgraded one. They usually replaced them when the clutch was changed.

The 4th shop I spoke to was a certified LNE IMS installer whom stated that if you get to 50000 miles you probably wont have a problem and you could wait until you do a clutch change but they did relay a concern about low mileage cars which have a tendency to not be maintained well and could have had acidic oil in them wearing out the seal of the bearing and suggested it be good to change it now. However they never indicated whether or not that they pulled a bad bearing out of a low mileage car.

Given I’m OCD about the issue I will probably end up replacing this sooner than required and keep my near mint condition Porsche 996 for a long time. I will put good money on the bearing being in good condition when I change it out. I will post pictures of the original bearing when I get the IMSB changed out.

I just don't know if the LNE bearing options ($600 Single Row Pro to $1600 - IMS Solution Roller Bearing) are better than the EPS cylindrical bearing with pressure fed oil for $485. Thats a big difference in price and of course both LNE and EPS state their products are flawless.

 

"I just don't know if the LNE bearing options ($600 Single Row Pro to $1600 - IMS Solution Roller Bearing) are better than the EPS cylindrical bearing with pressure fed oil for $485. Thats a big difference in price and of course both LNE and EPS state their products are flawless"

I have no opinion, informed or just a WAG, either way. I have not bothered to research these IMSB upgrades to the point could arrive at a point I could make a decision I could be comfortable with.

There is I seem to recall plenty of back and forth by LNE and EPS regarding which solution is best. The back and forth gets hot and heavy too sometimes as others chip in their 2 cents worth and it is hard to read though the posts to find the nuggets of gold in among the mountains of iron pyrite.

 

Is there a website to enter your vin number to see if your vehicle falls into the IMSB issue range? I have a 2006 997S with 41,000 miles.

 

Don't think you can enter your car's VIN, but there's this website -- not sure if it is an official site or something somebody else set up -- that provides some info.

http://www.classactionrebates.com/settlements/porsche/

The info at the site says the years involved are May 4, 2001 and February 2005 so you will have to look at your car's manufacture date -- should be on a tag on the door -- to know if at least your car's in the right time frame.

Then you have to look at the VIN numbers to see if your car's VIN is included.

 

MACSTER - Thank you for the info... GREAT NEW for me my 2006 997S doesn't fall into the manufacturer dates... I'm outside the dates by nearly a full year.

 

An alternative approach is to google a little :
fit a "Guardian" metal detector(LN Engineering)
Get UOA from Driven Oil ,not Blackstone/Cat
That 'should' give you advance warning of IMSB and other problems. Hopefully it will be a much less intrusive peace-of-mind approach