Engine will not stay started

2000 GMC SIERRA
150,000 MILES
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DAISYGIRL8688
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The car cranks, starts and then shuts off. Replaced fuel pump relay but same symptoms. You can hear the pump running for 1 second after the key on. I would like to see the wiring diagram at the relay. Suspecting pump or filter. What do you think? I would also like the procedure to remove the tank. Thanks!
May 17, 2022 at 9:31 AM
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STRAILER
  • Experienced Mechanic
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If you can upload a video of what the engine is doing, we can tell what's wrong. In the meantime, there could be a vacuum leak, or the throttle body is dirty causing the stalling problem. Here are some guides that can help us see what's going on and fix the problem. I have also included the fuel pump wiring diagrams so you can see how the system works.

https://www.2carpros.com/articles/stall-at-idle

and

https://www.2carpros.com/articles/how-a-throttle-body-works

and

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.
May 18, 2022 at 5:12 AM
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DAISYGIRL8688
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  • 57 POSTS
Hi,

I sprayed some starting fluid into the throttle body and the engine ran for quite a while, so I definitely have fuel delivery issue. Before removing the fuel pump, however, I will try replacing the fuel filter and checking the ground for the fuel pump. In the electrical diagram you sent (thank you!) it shows ground for the pump is "left frame body mount bracket" G400. Would you know specifically where this is?

Coincidentally the fuel gauge is not working either, but it does not show common circuitry with the pump.

Also, the fuel pump assembly was replaced 5-6 years ago. Is it common for these to go bad so soon?
Thanks!
May 19, 2022 at 12:00 PM
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STRAILER
  • Experienced Mechanic
  • 55,273 POSTS
I am not sure about the ground location exactly, but if you look around, I know you can find it. If the fuel pump was not replaced with an AC Delco unit, then yes 5 years is about how long aftermarket pumps last. Here are instructions in the diagrams below to help you change the pump out. Check out the diagrams (below). Please let us know what happens.
May 20, 2022 at 12:23 PM
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