low fuel pressure?
Thread Starter
Le Mans Master
Joined: Nov 2009
Posts: 6,882
Likes: 234
From: Bangkok, Thailand
low fuel pressure?
I finally got to my fuel pressure gauge today and check the 91. The highest pressure I see is after shutoff at 41 psi. It does hold pressure steady after shutoff. While running at cruise rpm pressure is steady at 35. I didn't see it go above 37 at any point while it was running.
Sound like fuel pump time? I have a new filter but haven't changed it yet. I recall these filters being just a screen inside. Could there be so much crud in the filter that pressure is being reduced? Gawd, I sure hope not.
Sound like fuel pump time? I have a new filter but haven't changed it yet. I recall these filters being just a screen inside. Could there be so much crud in the filter that pressure is being reduced? Gawd, I sure hope not.
Suckin' gas, haulin' ass.
Joined: Apr 2010
Posts: 1,100
Likes: 8
From: Newport News Virginia
I would change the filter and see what you get. The higher pressure while the engine is off kinda of says to me that while running, there is some blockage between the filter and the pump, and when the motor is off the pump catches up just a bit before shutting off.
Race Director
Joined: Nov 2003
Posts: 12,220
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
FP should be higher with the engine shut off. Consider that injectors running (firing) are like a controlled leak in pressure.
Mine is 34lb/in when running. No problems with that pressure and a 383.
Mine is 34lb/in when running. No problems with that pressure and a 383.
Safety Car
Joined: Sep 2001
Posts: 4,146
Likes: 541
From: Glenbeulah Wi
running engine vacuum reduces fuel pressure, your pressure seems fine to me. What is the pressure when you disconnect the vacuum regulator line? It should be around 43 psi when running and at WOT.
