Fuel pump not working correctly

[dustinwinkle]

I have a fuel pump problem and I don’t know where to start looking. When I turn on the key, the fuel pump does not run. It does not matter how long I leave the key in the on position, the pump does not run. After I crank the engine for about 10 seconds the pump will start and the truck starts and runs fine. It does it every time I start the truck.

If I start it right after I turn it off it starts right up since there is still pressure in the system. If I hook up the fuel pump test circuit before I start the truck it starts up fine.

Any clues??

Thank you,
Dustin Winkle

 

[NecroWolf]

Re: Fuel pump not working correctly

i think that sounds like the fuel pump relay. if the pump comes on after oil pressure builds up that means the backup is turning it on

 

[Don W.]

Re: Fuel pump not working correctly

Check fp fuse first ECMB I think, then:

OK, then transcribed from the manual the sequence is: (no guarantee as to my typing accuracy)

Ign off
connect test light between "test" term and ground.
Key on
Light should come on for 2 secs.
(if it does then relay is ok)
If not then:
Disconnect relay
Connect test light between relay harness term "1" and ground
Light "off?" - fuse
Light "on?" - connect test light between "D" and "C"
Light "on" - Relay bad
Light "off" - open ground

There's more but it gets into the relay itself and/or the the oil pump sw and/or bad grounds. I'd almost bet on the fuse.

 

[dustinwinkle]

Re: Fuel pump not working correctly

Thanks guys. It was a bad relay.

 

[ABOSS]

Re: Fuel pump not working correctly

I am new and think i have the same problem, can some one tell me we to find the ECMB and fuel pump relay tahnks!! did many seraches all i found