The factory pump went out on me about a month ago, started getting a code 54 after replacing the pump.

The car runs great once started, but its a bitch to start. The pump doesnt prime, and I have to crank it for a good 5-10 seconds to get the car to start. The car started fine with the old (factory) pump just ran like *** (started sputtering after about 3k rpms).

I've spent the past couple of weeks trying to fix the issue but nothing seems to affect it. Sofar the car has a new pump, sending unit, wiring harnes (the one that goes from behind the rear seat to the sending unit), new filters, new relay, and a new fuse (the one near the battery).

I cleaned up the harness going to the relay with a spray can of electrical parts cleaner as it was fairly dirty, there is a little bit of exposed wire at the bottom of the connector but not enough sticking out for the wires to contact each other.

Ive reset the ecm everytime ive worked on it, but the code 54 always returns. I've searched the forums for code 54, but nothing seems to quite fit my car. The wires going to the relay connector are all green, save for the black ground wire.

 

Code 54 for an MPFI is a 'low voltage to FP' code. I'm betting it's a bad FP relay. ( be sure to check it's ground wire ! ) This is from the 86 Shop manual:



That should help get you past this problem !