Fuel Pump Not Turning On

[usamarshal]

Have a 2000 Chevy Tahoe Z71 with old body style. Has a 5.7 engine with 4 wheel drive. Just changed out my fuel pump three weeks ago, along with new relay, and fuel filter. Also made sure to clean out the gas tank too. The fuel pump wiring harness was replaced four years ago at dealership. She ran like a champ the last three weeks, then when I tried starting it again last night...nothing...she'll turn over fine, but the fuel pump won't turn on and there isn't any fuel pressure.

Basically, there was no indication of anything going wrong with fuel pump. The fuel tank was 3/4 full, so I know the fuel pump isn't frying on me. Tried disconnecting the battery cable for about a half hour, still nothing. I cleaned the fuel pump ground and put a new ring terminal on the ground wire. Even got another relay...nothing. Any help with this would be appreciated. Just getting sick of this fuel pump issue. Thanks, Skip

 

[95TwinTT]

Well, the obvious things to check would of course be the wiring around the fuel tank. Is the + 12 reaching the pump?

Did you recently fill the fuel tank again? How about the fuel gauge, is that working properly? Did you have any trouble inserting the fuel pump back into the tank, you know, as far as the float and hoses and wires, etc?

When you mentioned cleaning out the tank, how did you do that. Was the plastic box firmly in place around the fuel pump? Did you use a stock GM fuel pump?

Sorry about the 20 questions here, just trying to get a mental picture of the situation.

 

[98hoe]

My buddy had the same problem. Ended up being something with the distributer. Might wanna check your spark. See if they are all firing properly. My friend had a weak and slow spark. Good luck!

 

[usamarshal]

I don't believe its a spark issue because I've already tested for fuel pressure and there is none. You also can't hear the fuel pump turning on what so ever.
But yeah, I'll need to check to see if my wiring is alright. From what I see the fuel gage looks to be working. Its still at 3/4 full when I filled it up the other day. No troubles inserting the fuel pump in the tank. No crimping in the hoses...everything went smoothly. When I cleaned the tank I just syphoned all the gas out. Put fresh gas in and syphoned it out again...worked really well. And yes it was also a gm fuel pump...I believe it was AC Delco.

Well, the obvious things to check would of course be the wiring around the fuel tank. Is the + 12 reaching the pump?

Did you recently fill the fuel tank again? How about the fuel gauge, is that working properly? Did you have any trouble inserting the fuel pump back into the tank, you know, as far as the float and hoses and wires, etc?

When you mentioned cleaning out the tank, how did you do that. Was the plastic box firmly in place around the fuel pump? Did you use a stock GM fuel pump?

Sorry about the 20 questions here, just trying to get a mental picture of the situation.

My buddy had the same problem. Ended up being something with the distributer. Might wanna check your spark. See if they are all firing properly. My friend had a weak and slow spark. Good luck!

 

[95TwinTT]

I would take some zip cord and hook up +12 and ground, using clip leads. I would try hooking up to the fuel pump itself. Or as close as you can get to it and see if it will turn on with the external power source.

I always suspect grounds to be a problem after the vehicles have a few years on them. Especially if they are near salt water, or if the truck is parked near a lake or river.

I'm in Minnesota, so we have the added burden of salt from the roads. If that does nothing, about the only thing left is "infant mortality" of the new pump. Let's hope that is not the case.

Good luck.............:sad: