94 c1500 no fuel pump signal. Cranks but not start.

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PlayingWithTBI

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I’m guessing this pump, despite have less than 30 minutes of runtime is faulty. I’m thinking I’ll try to hunt up a Delco pump if I can find one.
It could be. That's not unheard of. I'd clean all my connections including grounds there around the sending unit before spending more money on another pump.
 

Alexcantsleep

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Ok peeps, I’m at a loss again.

so I pulled my tank today, which is brand new. Pulled off the new but faulty fuel pump.
I installed a brand new, ac Delco pump. Genuine, out of the box.
Gig it installed, added some fresh gas and turned the key on. The pump primed! So I turned the key to start and it fired right up and ran like a champ. Revved ok, idled smoothly.

It ran for two minutes.
Then it quit.

same issue. Started right up with carb cleaner but the pump isn’t pumping. Ran a line direct from a hot 12 volt source to the pump and nothing. And of course checked all my grounds all that, again...all is normal.
So what would cause two brand new pumps, one being an actual Delco, to fail back to back in a matter of minutes? Voltage is all normal, it doesn’t seem like it’s getting too much or too little current. I’m stumped. Honestly if Onhadnt already boot the new battery, tank and tires I’d just get rid of it.

I’m thinking I may run an external pump and wire it independently of anything else.

Not sure what else to do but I need this thing out of my shop now.
 

Schurkey

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It ran for two minutes.
Then it quit.

same issue. Started right up with carb cleaner but the pump isn’t pumping. Ran a line direct from a hot 12 volt source to the pump and nothing. And of course checked all my grounds all that, again...all is normal..
HOW are you "checking" the grounds? I would be testing for voltage on the pump ground wire, as close to the pump as practical. One volt is about typical, but less is better.

You string a new wire from 12V + to the pump? Or from 12V + to some other point on the wire harness? Did you ever try connecting a fresh wire from battery NEGATIVE to the ground side of the pump?

Did you replace the in-tank wire harness? Typically about $20. Doesn't do any good to put 12V OR GROUND at the external wire harness if the in-tank harness is junk (and that's common.)
 
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