I have a 89 that had a 2.8l mfi to which I am putting a 350 TPI (originally a 305) from a 86 TA. I have the donor car and the wiring, however it is rough and in many pieces.

I first thought the swap would be easy in terms of wiring. I intended to retain the engine harness from the 86 and hope it would mate with the 89, however it seems there are significant differences between the 86 to 89 year. My first stumbling block is the fuel pump wiring, it seems the 86 fuel pump wire runs from the harness at the ECM end, but the 89 runs from the firewall connector end, but there is no provision for it on the 86 harness.

This is the first thing I noticed because as I tried to start the car the fuel pump didn't come on. I am wondering what else may be different? I know the windshield wiper and hvac power (which are on the engine harness for some reason) are different.

My debate now is should I try source and reroute every connection that may be different, or replace the interior harness in the 89 from the 86, or try and make the 89 (2.8l V MFI) engine harness work with the TPI?

Any insight would be appreciated.

Mike

 

find a TPI harness from an 89 donor car. the TBI harness and ecm wont work.