Got the scary yellow engine warning light (visit workshop), mind you this is a brand new engine with only 3k miles on it, so I hooked up my Duramtric cable and got the following fault codes:

P2187: oxy sensor control RKAT bank 1 range near idle speed
P2177: mixture adaptation checksum error bank 1
P2189: oxy sensor control RKAT bank 2 range near idle speed
P2179: mixture adaptation checksum error bank 2
P2096: A/F ratio correct. beh cat. c. bank 1 above lean control limit

The only engine mod is an EVOMS CAI, which is very benign. Do you think that perhaps the fix could be as simple as cleaning the MAF sensor?
CATTMAN

 

Did you reuse your old oxygen sensors on the new engine? If the CAI uses oiled filters I might start with cleaning the MAF sensor. It's cheap.

 

Spoke to Porsche tech, who happens to be a friend
He recommended using my Durametric to log Actual Values at idle and record the RKAT readings. The variance is -4 to +4, and it ought to be at 0.

He recommended that I do this before cleaning the MAF, which I will do tomorrow (I'll drive the '87 show car to work tomorrow) and report back.
CATTMAN