I just finished a 94 LT1 drivetrain into my 79 malibu, and I have run into one serious problem. For some reason the 4L60 is in limp mode, but the car runs great as far as idle and such. Could it be throwing a code and just not show it? the reason I wonder, is because it looks to me like the painless harness uses an OBDII serial port...but if Im not mistaken, the 94 PCM is OBD1. would this stop my SES light from coming on? Would it hurt me to try an OBDII computer? I have access to a 95 impala PCM to borrow, this wont hurt anything will it?

 

95 impala is still OBD1. as for your question i don't have an answer but just wanted to let you know hehe