My 93 351W has 0 PSI at the fuel rail with the key on and engine off. I hear the fuel pump whirl for a second or so after turning the ignition on but still no pressure. The engine will start after it cranks for a turn or two and I get about 30 PSI at idle or 2500 RPM. Starting is increasingly difficult if the engine is warm taking at least three or four cranks before it cathces. Upon turning the engine off the rail pressure drops back to zero almost instantaneously. New fuel filter less than a thousand miles ago.

No fuel system related codes are present.

Other than that she runs fine but is really sluggish lacking acceleration.

Do I have a bad pump or a bad fuel pressure regulator or all of the above.

 

since you have a gauge already go buy you a haynes manual # 36058 $12 it has all the deiagnostic procedures to determine if its the check valve in the pump or the regulator, or injector. it will save you a lot of guess work. DW