Fuel pressure spec needed

2003 CHEVROLET SILVERADO
246,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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HD2424
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Can someone tell me the fuel pressure spec is for my truck listed above 1500 z71?

I need specs for;

Key on engine off.
Key on and engine running.

Thanks
Jun 28, 2022 at 3:46 PM
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JACOBANDNICKOLAS
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Pressure on this is different based on the VIN. The 8th digit in is the engine code. If you look below, they only provide the pressure when the pump is commanded on. So, that would be engine off. It will drop a little with the engine running, but I wouldn't expect more than 5 PSI.

First, identify the 8th digit in your VIN and then refer to the attached pic.

I hope this helps.

Take care,

Joe

See pic below.
Image (Click to enlarge)
Attached Media
Jun 28, 2022 at 10:28 PM
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HD2424
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Yes, tested I had 49 PSI key on engine off and 49 engine running. I guess this this is problem with random misfire.
Jun 29, 2022 at 5:57 AM
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HD2424
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Thanks for your help got pump ordered.
Jun 29, 2022 at 5:57 AM
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JACOBANDNICKOLAS
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Hi,

You are very welcome. I assume the engine code is not Z. LOL As far as replacing it. Here is a link that explains how in general. If you need any of the specifics, let me know if this is a regular cab or extended:

https://www.2carpros.com/articles/how-to-replace-an-electric-fuel-pump

Take care and feel free to come back anytime in the future.

Joe
Jun 29, 2022 at 9:31 PM
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HD2424
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Extended cab.
Jun 29, 2022 at 10:22 PM
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HD2424
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I’ve cut a trap door in bed and can change pump in 10 minutes. I sealed the seams and have a heavy rubber mat that covers the bed. I don’t know why Chevy doesn't build them that way.
Jun 29, 2022 at 10:33 PM
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JACOBANDNICKOLAS
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Hi,

That is the way to do it. LOL Let me know how things turn out for you. I'm interested in knowing if it takes care of the issues.

Take care,

Joe
Jun 29, 2022 at 11:31 PM
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HD2424
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Will do.
Jun 30, 2022 at 7:19 AM
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HD2424
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Okay, Joe. Heads up changed the fuel pump and fuel filter and starts right up, no more random misfire or knock sensor codes. test drove over 100 miles on trip I had to make ran great no codes of problems. Thanks for the help.
Jul 1, 2022 at 9:27 AM
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JACOBANDNICKOLAS
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Hi,

Thanks for the update. I'm glad to hear it's running good.

Please feel free to come back anytime in the future if you have questions. You are always welcome.

Take care and Happy 4th!!!

Joe
Jul 1, 2022 at 9:22 PM