I had been having trouble on start-up which ended up being the FPR. I replaced that and now the car starts instantly everytime hot or cold. I have the pressure set to about 42psi WOT. But now there seems to be a problem during accelration. It idles smooth and when maintaing a constant speed it is also smooth. But under any type of acceleration the engine, and car feels like it is shaking and there is a noticeable loss of power(although not extreme.) I tried playing with the fuel pressure, but there is no change all the way up to about 48psi WOT. The plugs were just replaced and my knowledge of this car is pretty limited. Please give me a few ideas on possible problems.

 

exhaust restriction

 

What would be the cause, and possible fix for that? Thanks for responding by the way.

 

From recent experience I'd start with the plug wires, especially since you mentioned you changed plugs. One or more plug wires may be damaged and arcing.

I had very similar symptoms, car would idle and part-throttle well (barely noticeable misfire occasionally) but opening up past 4K rpm it would stumble. I did a visual inspection at night w/ the engine running, sure enough electrical arcs galore. As I removed the wires I could see cracks in the outer insulation of the affected wires.

 

Thanks for the advice. I will definitely check the wires tonight.