fuel pressure reading.

[hi54lofi]

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Hello all, I am trying to determine whether my fuel pump is bad. 1997 k1500 5.7. I am not sure how to read the fuel pressure gauge. I have read that my pressure should be 60-66. Here is a video. Thanks for any info.

 

[Komet]

Gonna be honest here, I'm not sure I can read that fuel pressure gauge but I believe what I'm seeing is 58psi which sounds good to me.

 

[GoToGuy]

58 to 65, then down to 54 yo 58.
You have hold the camera lens straight on and the gauge face flat toward lens. Bump cap covers print. Parralex can cause incorrect reading. Needle appears in area it actually is not in.

 

[WICruiser-97]

What makes you think your fuel pump is bad? Pressure testing is a good starting point but if the problem is maintaining pressure while deliveriing fuel it can be either a weak pump or a clogged fuel filter. Fuel filter is a lot easier to change and should be done periodically anyway.

 

[Carlosm86]

What makes you think your fuel pump is bad? Pressure testing is a good starting point but if the problem is maintaining pressure while deliveriing fuel it can be either a weak pump or a clogged fuel filter. Fuel filter is a lot easier to change and should be done periodically anyway.

98 5.7, with key on I get 55-57 psi then slowly comes down with key off 10-15 psi after about an hour after key off. Is this normal?

 

[Schurkey]

98 5.7, with key on I get 55-57 psi then slowly comes down with key off 10-15 psi after about an hour after key off. Is this normal?

IF (big IF) the gauge is accurate, 55--57 is a little on the low side. I'm more concerned with the loss of pressure within an hour.

 

[Carlosm86]

IF (big IF) the gauge is accurate, 55--57 is a little on the low side. I'm more concerned with the loss of pressure within an hour.

Sounds good, I’m just a using a harbor freight fuel gauge setup. Currently dealing with hard start when engine is in operating temp. Perfectly fine when cold. Brand new Delphi pump, fuel filter, and spider upgrade.

 

[TXStepside]

i have a 97 5.7 vortec, replaced spider injection, pressure regulator. fuel filter all ac delco and am getting 50psi key on engine off, then running high 40s engine on. after the engine is off she drops to 40 within 2 mins. what do you think? regulator or pump? i just replaced the regulator 2 yrs ago and havent driven it much, are these known to fail in such a short time?

 

[Schurkey]

1. Is the pressure gauge accurate? How do you know?
2. All those pressures are low.
3. No way to know what is wrong without further diagnosis. Download the service manual set for your vehicle and follow the diagnostic procedure.