Ok, I've got a number of stock LT1 pcms laying around. I know some are from '96 and some are from '95. I was too stupid/lazy to label them. How can I distinguish them now?

Thank you.

 

The service number on the OBD1(95) end in 8051. I dunno about the 96s but you can use the process of elimination on those I guess.

 

Yes, I can do that. Thanks for the info.

 

The part numbers for the LT1 ECM/PCMs are:
93=16159278 OBDI
94=16188051 OBDI
95=16188051 OBDI
96=16214399 OBDII
97=16242921 OBDII

 

Or if you don't have any labels at all, you can crack open the case, and find the chip labeled "FLASH" on the Blue/Gray board.

If it says AN28F512, then it's an OBD1 PCM.

If it doesn't, it's an OBD2 PCM.

To distinguish between the 96 & 97 PCMs requires pulling the VIN out of them (powering it up and talking to it).