Fuel pressure

2003 CHEVROLET SILVERADO
200,000 MILES • 4.8L • V8 • 2WD • AUTOMATIC
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PSAGELY
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Vehicle is hard to start sometimes cranks first time. I have replaced fuel pump twice, the pressure reads 50. I do not know what the exact specs are.
Can the fuel regulator reduce the pressure? What else can I check to improve the truck starting without having to turn key several times to crank?
Sep 17, 2018 at 6:39 AM
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ASEMASTER6371
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Good morning.

What is the 8th digit of your VIN?

There are two pressures one for each. There are 2 4.8.

One is 48-54 and the other is 55-62.

Roy
Sep 17, 2018 at 6:43 AM
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PSAGELY
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I will get the answer this evening, cannot get to truck now. Thank you.
Sep 17, 2018 at 6:49 AM
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ASEMASTER6371
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Okay, sounds like a plan.

It is a good possibility that you got the wrong fuel pump.

Roy
Sep 17, 2018 at 6:53 AM
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PSAGELY
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Installed AcDelco pump.
Image (Click to enlarge)
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Sep 17, 2018 at 8:41 AM
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ASEMASTER6371
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Okay, still depends on the motor. There are 2 4.8 with different pressures for each engine.

Roy
Sep 17, 2018 at 8:49 AM
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PSAGELY
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The eighth digit is V.
Sep 17, 2018 at 12:40 PM
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ASEMASTER6371
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The fuel pressure is too low.

Chances are you got the wrong fuel pump when you bought it. They may not have asked you what you eighth digit was in the VIN.

Roy

Except VIN Z .................... 385-425 kPa (55-62 psi)
Sep 17, 2018 at 2:43 PM
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PSAGELY
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Okay, thank you.
Sep 17, 2018 at 2:48 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Sep 17, 2018 at 2:51 PM