Looking to purchase an early 997.1 IMS issues. Anyway to check on the condition or possible upgrade done to the IMS during a PPI?
Does looking for a 997.1 S eliminate the concerns? Any other models besides the 997.1 TT (..just sold mine) help avoid the problem?
Love the 997 series, but this IMS issue is worrisome. Thanks for all the advise. Serial # cutoff might help me too! Welome any thoughts.

 

Any of the Mezger engines like those in the TT or GT cars don't have the issue. 2009-2012 997.2 cars also don't have the issue.

2006 -2008 cars have the larger, non-problematic bearing.
​​​​​​You can schedule the engine serial number to see what bearing it likely came with. If a smaller bearing, that's doesn't mean it wasn't upgraded, but you can't really tell without records or removing the transmission. LN Enginneeing probably keeps a database of their bearings and what engine number and VIN cars they've gone into. If you find a car with a smaller bearing motor serial number, you could probably send the engine serial number and VIN to Charles at LN and they'd tell you if they've sold a kit for that motor.There are three different serial number types for the three engine variants in our cars - base model M96.05 3.6L engines, S-model M97.01 3.8L engines, and the X51 power kit M97.01S 3.8L engines. All three have slightly different engine serial number formats.

For S-model non-X51 M97.01 engines the serial number is of the format M97/0168YXXXXX. The last 8 digits matter and are the following format:
685XXXXX = M97 for MY05
686XXXXX = M97 for MY06
687XXXXX = M97 for MY07

So the first two digits are 68, followed by the year digit, followed by a five digit serial number. But the full serial is M97/0168YXXXXX.

For X51 engines I believe the format is M97/01S68YXXXXX (added 'S' between 01 and 68).

3.6L base engines have a similar format M96/0569YXXXXX (not positive on the 05, can someone check?).

With replacement engines there is an 'AT' in front of the final eight digits. So a S-model 3.8L factory replacement engine the format would look like M97/01AT68YXXXXX.

For 3.8L motors, up to M97/01 68509790 has the smaller IMS bearing and Engine number from M97/01 68509791 has the larger revised IMS.

For 3.6L motors, if the engine s/n is M96/05 69507476 and up it has the larger bearing.
THese days, the bigger concern with the 997.1 cars is bore scoring. It's more common in the S cars than the base cars.

 

My 997.1S was made in August of 2005, so probably one of the last of the 2005's. My understanding is that cars made after about Feb. of 2005 had the larger bearing so mine should have that. Can you confirm (or not)? - Thanks

 

Wow Petza914!
Best and most thorough reply I've ever received since joining this community. Thank You so much. Saved me hours of research!
Is It out of line to ask a seller /dealer to send you a pic of the engine serial # if no records of IMS replacement/upgrade can be found?

 

Not out of line at all. Also, there's a much more active 997 forum over on Rennlist if you want to join there as well. I'm the same username over there too.

 

You're always spot on with unmatched knowledge about these cars but is this a good assessment of the -06 -08 cars? Much improved over the earlier models no doubt but they still have the bearing and there are documented IMS failures on -06-08 cars. Few and far between for sure but still a possibility.

Just me but I would use "non-problematic" referring to high quality upgraded bearings like yours or to -09 cars or later where the bearing was eliminated.