Fuel pump

[Baylee Brown]

My 1999 2 door Tahoe suddenly shut off while driving in the middle of an intersection... and didn’t start back up. It turns over fine but doesn’t start. With the common problem for this model being the fuel pump, I replaced it and the relay. It still doesn’t start. Any ideas on what else it could be? I do not hear the new pump turning on. New filter installed as well.

 

[bsamole]

Check the OBD2 codes. My 99 did a similar thing. The code indicated faulty crank sensor. I replaced the crank sensor and it solved the problem.

 

[Doubeleive]

icm (ignition control module), check if you have fuel pressure first, auto parts store may be able to test the icm to verify, it's under the intake housing passenger top side engine

 

[drakon543]

first up did you recheck the pump change? just asking as you stated you cant hear the pump and you just changed it. disconnecting the fuel filter and cycling the key would be quick. check for voltage going to the pump. if it turns out you do have fuel check the distributor. they are also a common fail point on the 5.7. moisture in the cap can ruin the points in the cap real quick or bridge connections throwing the spark way off.

 

[OR VietVet]

I never did see if you checked spark before replacing the fuel pump. Did you? James and Wes are alluding toward that but I am curious and don't like to assume.

 

[dkknaebel]

When I replaced mine it wouldn't start back up. Ended up having to replace oil pressure switch. We could not hear the pump run either.

 

[NEECAPR]

First time I had any problem with fuel system('99 4 Dr Yukon) it was just like you describe--just not in every ones way. So much water had accumulated in the tank that the fuel line was all water at the supply line fitting by the firewall. After leaving it open, wrapped with rags, water purged and fuel came back. Water in fuel control system purged out after ten or fifteen seconds of cranking, then it starting up and cleared up quickly. Made it home with lots of newly purchased Dry Gas.

 

[mpyrol]

Check for fuel pressure 1st, then check for fire at the plugs. If the ignition module is bad it may prevent fuel pump from running. If you have no spark and determine the ignition module is bad, and it is in the distributor replace the distributor. The aftermarket ignition modules are no good. Companies that re manufacture distributors tend to use a good module for economic reasons. Oops looks like that module is external. Crank sensor shouldn't affect the pump. Use a timing light to check for fire at the plugs, if it has fire then move to checking voltage at pump. If it's a new pump it may be hard to hear running. It will cycle on and off with key on and off until it makes pressure.

Hope this helps

 

[Baylee Brown]

Thanks for all the help, the new fuel pump was defective. I got the defective one from advanced auto which was a car quest part but this time I ordered one from rock auto and it’s working.

 

[Jwc15]

Thanks for all the help, the new fuel pump was defective. I got the defective one from advanced auto which was a car quest part but this time I ordered one from rock auto and it’s working.

Wow I just found your thread here and I have the same issue. I dropped my tank and changed my pump with an advanced auto carquest pump and now it won’t start. My pump worked prior to this and I am replacing for other reasons since my tank was already down. This is terrible. Now how did you make sure the new pump was faulty? These are made in China and I bet they wired to the harness some mixed up way. The connector mated up though.

 

[79jasper]

Wow I just found your thread here and I have the same issue. I dropped my tank and changed my pump with an advanced auto carquest pump and now it won’t start. My pump worked prior to this and I am replacing for other reasons since my tank was already down. This is terrible. Now how did you make sure the new pump was faulty? These are made in China and I bet they wired to the harness some mixed up way. The connector mated up though.

Give a little more information.
What year? Engine? Model?
Did you try the relay?

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[Jwc15]

Give a little more information.
What year? Engine? Model?
Did you try the relay?

Sent from my SM-N960U using Tapatalk

2008 Chevy Tahoe 5.3 flex capable LTZ 4wd

Reason for dropping tank and cleaning it: noticed fuel fillups were getting tougher and pump shutting off after a few seconds (pressure). Bad charcoal cannister replaced, along with vapor vent valve solenoid, and purge valve up at the engine. Charcoal bits were everywhere in the evap lines and in the tank as well settled on the bottom. So three parts replaced there and blew out lines with compressed air. Since tank is dropped, replaced the fuel pump. (Pump was still working). By the way, those charcoal pieces going everywhere is a GM design flaw nightmare. I had charcoal pieces up at the engine in the purge valve. Tank cleaned beautifully and dried out, install new pump carquest from advanced and now getting crank no start. Tank is half full again to make things worse. I am dropping again and putting oem gm pump in and returning the one from advanced. I will make sure the wiring harness isn’t damaged supplying power to pump before new one goes in again.

 

[Jwc15]

inside fuse box, there is no relay or fuse in the spot for the fuel pump, and it ran fine without one somehow before this replacement pump. That is a mystery to me as I didn’t do that and I am second owner though. I read oil pressure sensor can act as that relay provider for the fuel pump?

2008 Chevy Tahoe 5.3 flex capable LTZ 4wd

Reason for dropping tank and cleaning it: noticed fuel fillups were getting tougher and pump shutting off after a few seconds (pressure). Bad charcoal cannister replaced, along with vapor vent valve solenoid, and purge valve up at the engine. Charcoal bits were everywhere in the evap lines and in the tank as well settled on the bottom. So three parts replaced there and blew out lines with compressed air. Since tank is dropped, replaced the fuel pump. (Pump was still working). By the way, those charcoal pieces going everywhere is a GM design flaw nightmare. I had charcoal pieces up at the engine in the purge valve. Tank cleaned beautifully and dried out, install new pump carquest from advanced and now getting crank no start. Tank is half full again to make things worse. I am dropping again and putting oem gm pump in and returning the one from advanced. I will make sure the wiring harness isn’t damaged supplying power to pump before new one goes in again.

 

[79jasper]

Iirc, there is a oil pressure switch that will cut power to the pump.
My 04 has the fuel pump relay in the box under the hood.

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[exp500]

JWC15- usually the netiquette is to start your own post thread. In the correct year range for your truck. Otherwise its hard to tell if a solution was ever found.