96-98 vortec 5.7 fuel pressure

[96z71sas]

Stumbles little when starting very hard in cold weather must cycle key fuel pressure is 55 key on drops to 50 after minute or so 47 psi at idle bad pump or regulator also when u Turk key off after running it goes back up to 55 then drops slowly to 50 looks little wet under regulator but don’t see drips any help would be great thank you

 

[MrPink]

sounds like a dying fuel pump. it should be at 58psi.

 

[JOHNGAAA1]

Fuel pump or clogged filter. Should be 58-62 psi.

 

[L31MaxExpress]

Fuel pump or clogged filter. Should be 58-62 psi.

62-66 if it has the OE spider.

 

[Schurkey]

Can't diagnose a bad fuel pump without taking a voltage reading on the wire harness as close as practical to the pump. Typically the connector on the harness just before it goes over the top of the tank. Then measure the voltage on the ground side of the harness, again as close to the pump as practical.

Low voltage to the pump--or high resistance/voltage on the ground side--will reduce fuel pressure.

Of course, with the way pressure is leaking down, SOMETHING is wrong with that fuel system.

 

[C30454]

Or the gauge...



Tom