Originally Posted by Satilite73


Question:

If I jump the fuel pump at the relay (with the relay in) to make the pump run, should it start while hot wired like this?


Just a long shot, all the relays in the under the hood box use the same relays. Did you try swapping the fuel pump relay for a different one (like the one for the wipers for instance, one you know works)? Maybe you just have a bad relay?

An answer to your question: Yes, as long as the relay has 12 volts to it, and the wire that feeds the pump is good. Usually, its the wire that supplies the 12 volts to the relay that fails, but I've also seen the feed wire to the pump fail.

If you have 12 volts coming into the relay: Remove the relay, run a jumper wire (make one about 3" long with two male spade terminals on it). Put one end of the jumper wire into the slot for the 12 volt power supply on the relay, and put the other end into the [censored] that the wire goes back to the pump. You should be able to hear the pump run. If the pump runs, the truck should start. You can drive the truck that way, but you will need to disconnect the jumper wire to turn off the fuel pump. If the pump does not run (since we know its good), the wire is broken somewhere between the terminal and the fuel pump. If you are really fed up with the whole deal, you can get under the under hood fuse box, and find that wire that goes to the pump from the relay, and run a whole new wire back to the fuel pump.

If you do not have 12 volts to the relay: Your truck has the under hood fuse & relay panel, there is a bundle of wires that go into that box. Follow them down to where the bundle splits. From memory (we know how that works right?), the bad wire splice is in the bundle of wires that turns back towards the firewall, about 6" or so from the bundle split, towards the firewall. Some of the wire bundles are warped in the non-sticky friction tape, and some are in the black plastic wire loom stuff. You are going to have to undo what ever is covering the wires to find the splice. A sharp razer knife will cut through the tape, but be careful not to damage the wires in the process of cutting the tape. Usually unwrapping the friction tape is a royal pain. I usually just cut the tape with a slot running along the length of the wires and peal it off like a banana skin. Your local auto parts store should have a roll of Friction tape, the last roll I bought was under $5 and it goes a long ways. Once the wire repair is complete, you just wrap the wire bundle back up with the new friction tape.

Your issue has to be one of these two things, provided the wire connection at the pump is good.

Last edited by poorboy; 07/18/21 10:04 PM.