I am putting a 1986 chevy iroc z mass airflow wireing harness and computer.in my 1988 tbi pontiac firebird. "I now have holley stealthram" My problem is i have no power to fuel pump or injectors or fan.I didnt hook up the 9th injector switch.I hope i can use this harness,i dont want to purchase a painless and have the same problem.

 

what kind of system did you have in your 88 before you began?

 

A TBI to TPI swap? Perform a search. It's been done a few times. Make sure the fuse for teh ECM/fuel pump is installed and intact (the one near the battery):

 

unless you have rerouted the wiring your firewall connection for the 86 and 88 are different. you will need to use an 88 harness for it to work. I am speaking from experience, I tried to use an 87 harness and I had the same problems. Found an 88 harness on ebay swapped it in and everything worked. The color codes are all the same but your pin locations on the firewall connection are slightly different.