Quote Originally Posted by GMPX View Post
That isn't correct, VIN change on the E92 works just fine. Often people get caught out on bench harness setups or conversions where they don't use an IGN +12V input and they switch battery power as well so when they turn off power the ECM loses all power.
The actual VIN change is committed to flash when the ECM is shutting down, not when the commands are sent. So if your power setup isn't correct (again assuming on a bench) then the VIN will never be updated in the flash memory.
I'll give it another try. The last E92 I tried changing the VN did not work, it would act like it changed but if you read out the tune again the old vin would be there. I have changed hundreds of VIN's on ls1b, e38, e40 and e67 with no issues.