Fuel pump not getting 12v
 

I did a bunch of searches on this but did not find the exact same situation I have so here is my problem.

I have a mostly stock 1990 GXL 5-spd with a stock 6-port n/a engine. I have an issue with the fuel pump not working. The car ran fine before I put it up on jack stands for three weeks ago to rebuild the front and rear suspensions, swapped rear sub frames, all new brakes, new bearings, new bushings, new parking brake cables, replacing the cats, etc… One of the last jobs was to change the fuel filter. So I jumpered the yellow connector to re-pressurize the fuel system, turned the ignition switch to ON, but the fuel pump was not running. I even pulled the stereo and both antenna fuses just to make sure I could hear if the fuel pump was running or not. The engine will crank but the fuel pump will not run.

I checked the continuity of the fuel pump pig tail harness connector at the rear left strut tower positive to negative leads and the pump checked out fine. So I wired a spare 12v battery to the fuel pump pigtail harness (positive to the black/white stripped and negative to the black wire) and the pump runs normally. I could hear it purge the air in the fuel system.

I bench checked the Main Relay and it functions correctly – and the continuity tested correctly. But when I plug the Main Relay back into the harness I can't hear it click on when I turn the ignition switch ON. I then tested the power supply (white) harness connector plug with the ignition switch ON and there is no 12v. Odd clue #1

So I removed and checked the Fuel Pump Resistor Relay – all the resistance is within spec. I thought maybe when I was patching the floor boards near the rocker panels I could have done something to the wiring harness. So I pulled the driver’s seat, trim and carpet and found were I had cut/drilled through the fuel pump power lead (blue stripped wire) and so I repaired it. That should solve the problem, right? No - still nothing.

I pulled the Circuit Opening Relay and also checked it for resistance – all is within spec. But when I checked the terminal voltage on the Circuit Opening Relay with the ignition switch ON; I did not get 12V on the Fc and B terminals. Odd clue #2.

Okay now I plug everything thing back together except the fuel pump pigtail harness - instead I plug in my digital voltage meter. When with the jumper wire in the yellow connector, I turn on the ignition switch ON and it only reads 0.15 volts. Odd clue #3

So now what do I do?

TIA.

Check the 15A "Engine" fuse under the dashboard. Sounds like it blew.

JV

Most likely the 15 amp Engine fuse.

Very interesting....fc3snantaku is having this exact same problem, the engine fuse was the first thing I had him check. It was fine. He also had a fuel cut switch which is getting power, but the pigtail connector in the rear is reading 0v-0.Xv. Perhaps your problems are one I'm the same...

I wish is was - the reason for my problem is that I was an idiot. When I removed the two fuses for the antenna (so that I could hear the fuel pump run) I removed both the fuses for "Antenna B" and "Antenna IG". Or so I thought. Apparently I did not stick my head in far enough to see what I was doing and mistakenly pulled the "Engine" fuse.

Thanks to SoloII//M (JohnV) for pointing that out to me - I owe you a beer!

She fired right up, idle and run smoother than ever. I let her idle a few minutes to burned off the oil on the new cats and pipes as well as to let the heat wrap smoke. Now I just need to re-bleed the brakes. The first ride was not long or fast since the brake pedal went straight to the floor.

Thanks again for all the quick replies!

Well, unfortunately for him, I guess your problems weren't similar after all, lol

If you happen to find yourself in Toledo this weekend, I'll be racing there Friday - Sunday. You know the place :) Maybe you'll bring me good luck like a few years back!