Not sure if anyone might be able to answer this. Customer put a flex fuel 02 tahoe pcm in a non flex 01 Silverado I believe. He originally just brought it to me and asked to turn vats off so it would start. Did that, and now it starts, I thought he had the right PCM and harness just PCM from another vehicle was his problem
Now he's saying it has the wiring harness from the 02 in it with the flex fuel plug just dangling... but its misfiring pretty good with 178 200 & 300 codes. Should I be able to do a reflash to non flex fuel program and it work ok? Not sure if there's any other differences in the harness and would need something in the harness changed?