I have a 93... 7427 ecu from a van 5.7
wiring harnes from a c1500 all wires Match ecu pin out
I have a 454 tbi and iac, Bought the wire adapter from eBay (crossover). Iac wasn't working
did the test and tbi reset procedure all I got was long cranking then a start and stop with a backfire..

did a voltage test on the iac wires weird thing is the two blue wires A-hi and A-low the voltage for each checked out correctly but they were reversed so I reversed them on the iac still won't work? Any ideas??