IMS in 997.1 Overblown?
12-18-2014, 02:00 PM
#1
Rennlist Member
Thread Starter
IMS in 997.1 Overblown?
Saw this interesting thread on Japolink from the owner of TrueDelta. The thread talks about he 996 and the issue of the IMS. The summary: After getting 200 owners of the 996 reporting on issues for the past 5 years - the writer believes the IMS issue in the 996 is way overblown.
While its only opinion based on his data points (TrueDelta is what he runs), I thought it was an interesting take on the IMS issue and how it has really hampered the value of the 996 on the marketplace.
Why I bring this up on the 997 thread is that to a certain degree the IMS concern has been brought up by potential buyers of the 997.1 and I thought it would be of interest to hear a recent report based on data from an on-going survey.
I myself was initially concerned about the IMS issue when I brought my 997.1 but after some research decided that it was fine and not a big issue for cars like mine (06-08 cars with the updated IMS bearing). I do admit I'm generally carefree about it since I got an 5 yr warranty that covers basically everything that can go wrong with my car, including an IMS issue.
The specific part I thought was interesting was the writer's comments about the 997.1 (when asked about that model from a reader) and how he felt the IMS issue is basically close to zero in his opinion:
Was located in the comment section:
We might have had a single reported failure for a 987 or 997. We don't have as many owners signed up for those, but based on the data we do have the failure rate probably isn't far from zero. Anyone should be able to sleep at night with one of those.
Interesting read.
http://truedelta.kinja.com/a-pin-les.../+tommcparland
While its only opinion based on his data points (TrueDelta is what he runs), I thought it was an interesting take on the IMS issue and how it has really hampered the value of the 996 on the marketplace.
Why I bring this up on the 997 thread is that to a certain degree the IMS concern has been brought up by potential buyers of the 997.1 and I thought it would be of interest to hear a recent report based on data from an on-going survey.
I myself was initially concerned about the IMS issue when I brought my 997.1 but after some research decided that it was fine and not a big issue for cars like mine (06-08 cars with the updated IMS bearing). I do admit I'm generally carefree about it since I got an 5 yr warranty that covers basically everything that can go wrong with my car, including an IMS issue.
The specific part I thought was interesting was the writer's comments about the 997.1 (when asked about that model from a reader) and how he felt the IMS issue is basically close to zero in his opinion:
Was located in the comment section:
We might have had a single reported failure for a 987 or 997. We don't have as many owners signed up for those, but based on the data we do have the failure rate probably isn't far from zero. Anyone should be able to sleep at night with one of those.
Interesting read.
http://truedelta.kinja.com/a-pin-les.../+tommcparland
Last edited by wardrive; 12-20-2014 at 01:51 AM.
12-19-2014, 09:20 AM
#3
Rocky Mountain High
Rennlist Member
Rennlist Member
I was one of the contributors of data for the 996. I changed my original factory IMSB to an aftermarket ceramic bearing when I had my first clutch replaced at ~120K miles. The original bearing looked very good and certainly didn't show any signs of impending failure.
I agree that the issue is overblown.
I agree that the issue is overblown.
12-19-2014, 09:25 AM
#4
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Drift over to the 996 forum for a taste of how out of hand the conversation has become. And don't trust a word Japolink says regardless if it leans to your point of view or not....the author of that bit has been on RL for the past 3-4 years using a very small amount of data to create his opinions....overblown yes.
12-19-2014, 09:43 AM
#5
Jalopnik needs to do a story on B6 S4 4.2 liter Audis, those things DO grenade quite a bit due to timing components that crack and destroy the engine. Same thing for the cam chain guides in the VR6 motor.
12-19-2014, 10:17 AM
#6
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I think if we're objective the IMS issue is not overblown on the 996. Porsche acknowledged this when it settled the lawsuit. While I personally do not own a 996, I worked in the car business several years ago and knew of several blown Boxster/996 engine failures. It's an engineering flaw, one which can be minimized and repaired, but a flaw none the less.
Even if the failure rate was 1% it would be too high. Imagine if 1% of Honda accords had a problem that caused the engine to grenade, it would be huge news. Personally, I'd never own a 996 unless it had a mezger engine. Just my two cents.
Even if the failure rate was 1% it would be too high. Imagine if 1% of Honda accords had a problem that caused the engine to grenade, it would be huge news. Personally, I'd never own a 996 unless it had a mezger engine. Just my two cents.
12-19-2014, 11:15 AM
#7
This article is from a Porsche Buyer's Guide regarding the IMS issue (draw your own conclusions):
ALL PORSCHE M96 AND M97 ENGINES from 1997
through 2008 have the potential for Intermediate Main Shaft
(IMS) failure although the risk continues to decline as the cars
get older. If you’re planning to buy a used Porsche of recent vintage,
it’s hard to avoid one of these cars and you need to assess
the risk associated with this potential problem.
There were three different intermediate shaft bearings used
in these model years. The first was a dual-row bearing used from
1997 through 1999 (the years cited are model years but you
might need to check your VIN number to determine which
group includes your car). The bearing from these years is less
prone to failure as the dual-row provided a higher load capacity
than the following version.
The next group of engines for model years 2000 through
2005 used a single-row bearing with less load-bearing capacity,
making it more prone to failure. This is the group that causes
the greatest concern and, considering the age of the cars, may
already have had the problem resolved, if it was going to occur.
The third group is comprised of engines from model years
2006 through 2008 which have a larger single-row bearing with
a higher load-bearing capacity and are considered equivalent
to the earlier dual-row bearings. This higher-capacity bearing
was designed to solve the higher failure rate of the previous
models but is still subject to failure, albeit at a lower rate.
The IMS bearing is a sealed unit with permanent lubricant
for the ball bearings. Although it is difficult to know exactly
how and why the failure occurs only in some engines, it appears
the seal erodes over time which allows engine oil to enter the
bearing and flush out the permanent lubricant. This results in
inadequate lubrication of the bearings which corrode and eventually
release metal shavings into the engine oil. This is a simplified
explanation, but if the problem is caught at this point,
it can be repaired. Because this is all occurring internally, the
only visual inspection which may give notice of the problem is
metal shavings in the oil. If the problem goes on too long, an
engine rebuild or replacement is in order.
How Great is the Risk?
Unfortunately, we don’t have a good fix on how many of
these engines are prone to failure. With the internet able to
publicize any person’s personal laments, we hear far more
about the failures than the engines that don’t experience the
problem. For the model year 2001 through 2005 group, it
appears the failure rate is more than 10%. This is based on
information in documents filed by plaintiffs’ counsel in a
class-action lawsuit against Porsche Cars North America Inc.
This recited that Porsche had already covered approximately
3100 claims under warranty or good will. There were an additional
3200 claims submitted to the settlement administrator
as a result of the proposed settlement of the lawsuit. For want
of a better number, if we assume there are another 1000 failures
that will occur, including future claims on the settlement
fund as well as cars that have been excluded from the settlement
class, the failure rate is about 12.6%, based on a total
class of 57,900 cited in the settlement documents.
We have no indication of the failure rates in the 1997-2000
and 2006-08 groups although the incidence is far lower than
that calculated above.
Assessing the Risk and Taking Precautions
What guidance can we give you when considering purchase
of one of these Porsches? There is no easy “yes” or “no” when
examining one of these cars, but let’s start with the first group.
These cars are all more than 14 years old. The IMS problem
occurs with miles and time; at this point, the potential problem
occurring within this group, should be minimal. That
said, it is still good to keep the problem in mind when buying
and/or maintaining your Porsche. Make sure any car you are
considering has full service records and if an IMS failure
occurred, that it was properly resolved. More frequent oil
changes are a further precaution that can protect against later
failure. If the Porsche you are considering has average miles
(6000-8000 per year), any problem within this group would
almost certainly have occurred. It is still wise to make your
maintenance decisions in conjunction with your Porsche
mechanic for best results.
There is greater risk in the second group (2001-05) because
of the higher incidence of failure. If our estimate of 12.6% as
the rate of failure is reasonably accurate, and considering that
almost all of these Porsches are at least ten years old, the chance
of future failure is relatively low. Keep in mind that this failure
only occurs in a limited number of cars. It’s not the type of failure
that will arise eventually in all cars if enough miles are covered.
Therefore, if you are considering the purchase of a Porsche
which has more than 40,000 miles on it and a review of the
maintenance records shows it has been meticulously maintained,
the risk is very low.
The risk for the third group, 2006-08, is similar to the first
group in terms of the likelihood of failure except the cars are
newer and haven’t had as many miles on the road. Still, all of
these cars are at least six years old and should have logged
enough miles to flush out most of the problems. These Porsches
are still young enough to qualify as CPO cars which could provide
another two years of warranty coverage if you purchase a
CPO car. An aftermarket warranty might be available if you buy
your Porsche from another source and could be a wise decision
if you are troubled by this potential problem.
Preventive Remedies
Aftermarket replacement bearings are available for the IMS
and some mechanics recommend installing one as a preventive
measure. Whether to pursue this course of action is an individual
decision to make with your technical advisor. The cost of a
replacement bearing and labor for installation appears to be
close to $2000. This is a small investment compared to the
rebuild or replacement cost of an engine should you have an
IMS failure, but you should keep in mind the low risk of the
failure happening. In some ways, this becomes more of an emotional
decision. If you coldly calculate the likelihood of a future
failure and measure it against the cost of a replacement bearing,
you’ll probably decide to assume the risk. If your concern
for the failure of the IMS bearing is more emotional and affects
the number of miles you drive your Porsche or the way you
drive it and enjoy it, then the preventive maintenance should
remove your worry and be a worthy expenditure.
ALL PORSCHE M96 AND M97 ENGINES from 1997
through 2008 have the potential for Intermediate Main Shaft
(IMS) failure although the risk continues to decline as the cars
get older. If you’re planning to buy a used Porsche of recent vintage,
it’s hard to avoid one of these cars and you need to assess
the risk associated with this potential problem.
There were three different intermediate shaft bearings used
in these model years. The first was a dual-row bearing used from
1997 through 1999 (the years cited are model years but you
might need to check your VIN number to determine which
group includes your car). The bearing from these years is less
prone to failure as the dual-row provided a higher load capacity
than the following version.
The next group of engines for model years 2000 through
2005 used a single-row bearing with less load-bearing capacity,
making it more prone to failure. This is the group that causes
the greatest concern and, considering the age of the cars, may
already have had the problem resolved, if it was going to occur.
The third group is comprised of engines from model years
2006 through 2008 which have a larger single-row bearing with
a higher load-bearing capacity and are considered equivalent
to the earlier dual-row bearings. This higher-capacity bearing
was designed to solve the higher failure rate of the previous
models but is still subject to failure, albeit at a lower rate.
The IMS bearing is a sealed unit with permanent lubricant
for the ball bearings. Although it is difficult to know exactly
how and why the failure occurs only in some engines, it appears
the seal erodes over time which allows engine oil to enter the
bearing and flush out the permanent lubricant. This results in
inadequate lubrication of the bearings which corrode and eventually
release metal shavings into the engine oil. This is a simplified
explanation, but if the problem is caught at this point,
it can be repaired. Because this is all occurring internally, the
only visual inspection which may give notice of the problem is
metal shavings in the oil. If the problem goes on too long, an
engine rebuild or replacement is in order.
How Great is the Risk?
Unfortunately, we don’t have a good fix on how many of
these engines are prone to failure. With the internet able to
publicize any person’s personal laments, we hear far more
about the failures than the engines that don’t experience the
problem. For the model year 2001 through 2005 group, it
appears the failure rate is more than 10%. This is based on
information in documents filed by plaintiffs’ counsel in a
class-action lawsuit against Porsche Cars North America Inc.
This recited that Porsche had already covered approximately
3100 claims under warranty or good will. There were an additional
3200 claims submitted to the settlement administrator
as a result of the proposed settlement of the lawsuit. For want
of a better number, if we assume there are another 1000 failures
that will occur, including future claims on the settlement
fund as well as cars that have been excluded from the settlement
class, the failure rate is about 12.6%, based on a total
class of 57,900 cited in the settlement documents.
We have no indication of the failure rates in the 1997-2000
and 2006-08 groups although the incidence is far lower than
that calculated above.
Assessing the Risk and Taking Precautions
What guidance can we give you when considering purchase
of one of these Porsches? There is no easy “yes” or “no” when
examining one of these cars, but let’s start with the first group.
These cars are all more than 14 years old. The IMS problem
occurs with miles and time; at this point, the potential problem
occurring within this group, should be minimal. That
said, it is still good to keep the problem in mind when buying
and/or maintaining your Porsche. Make sure any car you are
considering has full service records and if an IMS failure
occurred, that it was properly resolved. More frequent oil
changes are a further precaution that can protect against later
failure. If the Porsche you are considering has average miles
(6000-8000 per year), any problem within this group would
almost certainly have occurred. It is still wise to make your
maintenance decisions in conjunction with your Porsche
mechanic for best results.
There is greater risk in the second group (2001-05) because
of the higher incidence of failure. If our estimate of 12.6% as
the rate of failure is reasonably accurate, and considering that
almost all of these Porsches are at least ten years old, the chance
of future failure is relatively low. Keep in mind that this failure
only occurs in a limited number of cars. It’s not the type of failure
that will arise eventually in all cars if enough miles are covered.
Therefore, if you are considering the purchase of a Porsche
which has more than 40,000 miles on it and a review of the
maintenance records shows it has been meticulously maintained,
the risk is very low.
The risk for the third group, 2006-08, is similar to the first
group in terms of the likelihood of failure except the cars are
newer and haven’t had as many miles on the road. Still, all of
these cars are at least six years old and should have logged
enough miles to flush out most of the problems. These Porsches
are still young enough to qualify as CPO cars which could provide
another two years of warranty coverage if you purchase a
CPO car. An aftermarket warranty might be available if you buy
your Porsche from another source and could be a wise decision
if you are troubled by this potential problem.
Preventive Remedies
Aftermarket replacement bearings are available for the IMS
and some mechanics recommend installing one as a preventive
measure. Whether to pursue this course of action is an individual
decision to make with your technical advisor. The cost of a
replacement bearing and labor for installation appears to be
close to $2000. This is a small investment compared to the
rebuild or replacement cost of an engine should you have an
IMS failure, but you should keep in mind the low risk of the
failure happening. In some ways, this becomes more of an emotional
decision. If you coldly calculate the likelihood of a future
failure and measure it against the cost of a replacement bearing,
you’ll probably decide to assume the risk. If your concern
for the failure of the IMS bearing is more emotional and affects
the number of miles you drive your Porsche or the way you
drive it and enjoy it, then the preventive maintenance should
remove your worry and be a worthy expenditure.
Trending Topics
12-19-2014, 09:38 PM
#11
RL Community Team
Rennlist Member
Rennlist Member
Drunk in the South Bronx
A guy travels the NYC subway changing at 149th st Grand Concourse South Bronx at 3:00 AM drunk off his ***..... probably twenty times.
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
12-19-2014, 09:47 PM
#12
A guy travels the NYC subway changing at 149th st Grand Concourse South Bronx at 3:00 AM drunk off his ***..... probably twenty times.
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
I er ... eh?
For somebody so lucky in their travels you sure have taken it in the shorts on your motors. Or you have a large fleet of Porsches! Or you've used up your karma.
12-21-2014, 11:27 PM
#14
Race Car
A guy travels the NYC subway changing at 149th st Grand Concourse South Bronx at 3:00 AM drunk off his ***..... probably twenty times.
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
I er... um.... this guy was never robbed, stabbed, or beaten. Therefore, the South Bronx is the safest place on earth! The reputation is totally overblown and promoted as bad by fear mongers who enjoy terrorizing others.
...... talk among yourselves ....
I had two engines blow.
Peace
Bruce in Philly
12-22-2014, 11:12 AM
#15
RL Community Team
Rennlist Member
Rennlist Member
Two blown engines...
2000 Boxster S
1st blew at 47K miles - unkown failure, Porsche mechanic didn't think it was IMS
2nd blew at 150K miles on engine (197K on chassis) - My Porsche indy said it was an obvious IMS fail, new owner of car pulled the IMS and it was fine... actual failure reason unknown.
Don't kid yourself that a 911 is better or different. These engines are all the same, they are the same fundamental design. The only ones that truly are different are the GT3s and Turbos of that vintage as they used the old 993 block... the word at the time was Porsche planned to use the new block but...... couldnt' take it so they quickly reverted to the old on these models.
Anyone want to take a walk with me through the South Bronx at 3:00 after a pub crawl? I did it many time and it is fine.... just fine... trust me I have real, honest experiences.
Peace
Bruce in Philly
1st blew at 47K miles - unkown failure, Porsche mechanic didn't think it was IMS
2nd blew at 150K miles on engine (197K on chassis) - My Porsche indy said it was an obvious IMS fail, new owner of car pulled the IMS and it was fine... actual failure reason unknown.
Don't kid yourself that a 911 is better or different. These engines are all the same, they are the same fundamental design. The only ones that truly are different are the GT3s and Turbos of that vintage as they used the old 993 block... the word at the time was Porsche planned to use the new block but...... couldnt' take it so they quickly reverted to the old on these models.
Anyone want to take a walk with me through the South Bronx at 3:00 after a pub crawl? I did it many time and it is fine.... just fine... trust me I have real, honest experiences.
Peace
Bruce in Philly