1994 GMC Sierra 5.7L can't get fuel prime.?

[tornadochaser69]

I can not get my 1994 5.7L GMC Sierra engine to prime. If I squirt a little starting fluid in the throttle body it starts up and continues to run just fine. I used a noid light set and I am not getting a flash at either injector connection. I have installed a new relay on the firewall and even checked the fuse (also on the firewall) with no correction of the problem. Is there any other fuses or relays I may be overlooking?

 

[CactiJoe]

Throttle position sensor? Or the fuel sending unit/sensor in the gas tank?

Or the fuel pump isn't putting out the proper fuel pressure. You can check fuel pressure first under the hood.

Replace the fuel filter after the new fuel pump has run a couple of minutes. That way any residue in the fuel line goes out with the old filter.

Good Luck!

 

[Molson02536]

I can not get my 1994 5.7L GMC Sierra engine to prime. If I squirt a little starting fluid in the throttle body it starts up and continues to run just fine. I used a noid light set and I am not getting a flash at either injector connection. I have installed a new relay on the firewall and even checked the fuse (also on the firewall) with no correction of the problem. Is there any other fuses or relays I may be overlooking?

Start with the simple and replace your fuel filter, then inspect the ground wire to the fuel sending unit. The ground wire to the fuel pump in the sending unit is separate from the sending unit wire harness.

Most likely it's going to just be a dirty fuel filter, the fuel pressure to the TBI system is best ran at 13 PSI to 13.5 PSI. Good luck and keep us posted.