FUEL PRESSURE LOSS

[KEONE]

Whats up guys, I have the problem like alot of you other SHO owners where my car is very slow, hesitates and sometimes sputters in low RPMs. I checked the fuel pressure at the schreader valve and find that if I prime the fuel pump first by turning the key w/o starting it my pressure is @ 34-35 psi which I believe is normal but if I turn the car off or drive for a while, pressure drops to @12 psi. If there is anyone out there who has experienced this unnatural phehomenon and solved it I would appreciate some help over here.

 

[SHOguy 92]

get injector cleaner and change ur fuel filter thats my guesses.

 

[rangerj]

KEONE,

Check a service manual for your model year at your local library. I think your prime pressure should be 40 to 45 psi, and your running pressure should be 26 to 30 psi. You running pressure at 12 psi is definetly too low.

If the fuel filter has not been changed in 50K, it would be a good idea to change that first and see if it helps.
rangerj

 

[AutoSHO]

Idle: 28-32 PSI
No vacuum (disconnect and plug Vaccuum to FPR): 38-42 psi

Priming should be the same as no-vacuum, 38-42 psi. Mine typically primes at 42 psi, then when teh pump turns off drops to 38-36. This is with a new FPR. Also, when you pop the throttle open, the fuel pressure should immediately jump up, it should not stay low or lag behind the throttle opening.