I just bought a 93 Sierra that doesn't run and the guy told me he thought it needed a fuel pump. It cranks over but doesn't start. He said if you put fuel in the intake it runs for a bit but that's it. So I replaced the fuel pump and it still don't run. I can't hear the fuel pump prime when I turn the key on so I checked the fuse and that was fine. I went to the store and bought a new relay, put that in and the truck still won't run. I'm out of ideas on this thing. If the fuel pump doesn't prime, it has to be electrical but if the fuse, relay, and pump are all good I don't know what to do next. Any help would be much appreciated.

Thanks

 

Some models have a ground on the top of the frame around the tank area. The wire tends to break or the ground is too rusted.
If that's not the problem, use a test light or multimeter to check the hot wire at the tank. Then you will know if the problem is inside or outside the tank and can diagnos further.

 

I relocated both grounds (the one for the pump and the one for the filler tube) and pump still won't turn on. I don't have a multimeter or a light so I don't know how to check if I'm getting power to the pump. I assume I'm not cause it's not turning on and the pump is brand new. Is there any way I can jimmy rig this thing. It's just a plow truck. Can I hard wire the pump somehow so it stays on all the time and then I'll just take the fuse out when not in use. Is that a possibility?

 

You can jump power to the fuel pump and see if it runs. Not smart to leave it that way. If your in an accident you don't want the pump to keep pumping.
These issues aren't too hard to track down. A test light is only 5 bucks. Alot cheaper than throwing more parts at it.
Google a wiring diagram for your fuel pump.