Heya folks,
I have a 2004 mustang GT with a P-1SC Procharger Blower, 42lbs injectors, and fuel pump that came with blower kit. Everything else is stock. I'm going to put on a Magnflow exhaust here in a couple days. When I'm in 3rd or 4th gear and stepping on the gas, my speed will increase, but as the RPMs go up, the engine will feel like it is fluttering. It's hard to explain. It really cuts into the power. I took the car in to Ford, and they say the fuel pressure is good. I got a Diablo Predator that will watch the computer real time, and as I watch the fuel pressure that the computer is seeing, I see the pressure jumping all over the place when I'm mashing the gas peddle. 50lbs to 25lbs to 34lbs....etc. All in a matter of a few seconds. No, I don't have fuel or boost pressure gauges yet, they are next on my list.

I'm wondering if whatever sensor that monitors the fuel pressure maybe bad. Also, when I turn the ignition on, I used to hear the hum of the fuel pump for a sec or two. Now, I hear the fuel pump and then when it turns off, and soft crinkling sound. Almost like a plastic bag being balled up, but of course very faint and for only half a second.

Also, if I disconnect the waste gate from the vacuum pressure line, and close the line up, and try to run the car, the engine really vibrates badly, even at low RPMs. I tried that because I was trying to see if it might have been a vacuum leak with the waste gate or it's pluming.

I've had the car for a year now, and put 4600 miles on it. I've had the Procharger on the car for 3 months, and for two months have had the problem. The first month the car ran great. Now, I'm bashing my head against the engine block trying to figure this out.

 

After a bit more investigation, the "crinkling" sound is coming from the engine compartment, no the fuel pump. Almost sounds like a relay chattering, or something arching for a moment. I'm not sure if that is normal or where it is coming from.