2003 GMC Safari, 120,000k, Auto. Cranks, but fuel pump doesn't energize, and fuel pump shows empty when full. Had new fuel pump and filter installed. No change. Mechanic says wiggled wire harness near fuse box (along with others), and fuel pump energized and van started. I had checked all fuses and relays, all good. I have an OBD EX for my laptop to use with OBD Wiz, but since won't start, I am at a loss. What would cause the fuel pump not to energize AND the fuel gauge show empty. Saw a Sonny video how to diagnose a short from the fuse box. Checked wiring harnesses, but couldn't find a short, doesn't mean there is not one that I couldn't find. Sprayed starter fluid in the air intake, would not fire. Bad PCM?
You need to check that the fuel pump fuse and relay are good.
(test with meter, or swap with another)
But based on the fact that jiggling wires helped, you have a wiring fault. Check continuity (in the FAQ)
https://carkiller.com/scottykilmer/qa/electrical-2/
If it doesn't start with starting fluid, then you probably have an ignition problem. Pull out each spark plug and test it.
Fuel pump electrical schematic
