Has this ever happened to anyone:

First off, a little background: I swapped a v-8 TPI into what used to be a v-6 MPFI. The computer still hasn't been keyed in yet and it's running a little rich. When I drive it around a while and then turn it off, it won't start because the fuel pump won't come back on line. I put in a new relay and it still does this. Can a TPI that’s running a little rich, flood like a carbureted engine? I do smell gasoline when I turn it off.

Anyway, today, I drove it around and then parked it. Sure enough, it cranked, but didn’t start. I unplugged the fuel pump relay and, with a test-light, I checked the harness to make sure the ECM was sending the fuel pump signal for 2 seconds when I turned the ignition to on - it worked; I tested the ground terminal - it was good; and the E terminal was hot.

I plugged the harness back in and tried jumping the G terminal on the ALDL with 12v to get the pump to turn on, but nothing happened. So I unplugged the fuel pump relay harness again and I jumped terminals A and E with a 20A fused jumper and nothing. Notably, however, I kept hearing a clicking on either my MAF relay or the MAF burn-off relay, which, for some odd reason, are both loose and next to my radiator by the passenger side wheel well.

By now, I got frustrated and started tapping the fused jumper wire from the E terminal to the A terminal in repetitive succession and VIOLA, the pump came on. I stopped; waited and then tried it again; same thing, clicking from some relay over by the wheel well. Then, like before, I tapped the two terminals a few times and whammy, it came on again.

I plugged in the relay harness, started the car and let it run; I then unplugged the harness to make sure it wasn't my oil pressure switch wasn’t the culprit and the car kept running, so I guess the oil pressure switch is okay.

I turned off the car and secured the MAF and MAF burn-off relays in an upright position to the fender; before they were just loose and on their sides (victims of the engine swap, I suppose). I put the ignition back in the on position and the pump charged up again. I even jumped terminal G with 12v with the ignition off to make sure that this wasn't some fluke and it worked.


I can't figure out what’s up with this car, it's like it's possessed.

Could the fuel pump be bad or going bad; I mean, by the time I got frustrated and started banging one terminal jumper into the other, a few hours had passed. Do fuel pumps act up when their hot and then work when they cool off? It’s a holley high flow made for the 1987 and up TPIs. I got it from Summit and I’ve driven the car like 20 miles (TOPS) since I had it put in 2 or 3 years ago.

ANY THOUGHTS???

 

With an intermittent problem such as that, the only ways to eliminate possibilites are to either replace everything or to catch the problem while it occurs and start checking circuit voltages. Make sure the FP relay is getting energized by the ECM, and the relay contacts are closing. Then make sure power is getting all the way to the pump.

 

Any thoughts on how to check to see if the juice is getting to the pump?