Lately I've noticed that when idling in park or drive, the RPMs will fluctuate a bit. It's not as noticable on the tach, but you can definitely hear and feel it in the car. I checked the fuel pressure gauge that the previous owner put on and its reading only 28 psi (eek!). He also installed an AFPR on the thing, however when I went and tightened the bolt on top to increase the fuel pressure, it only went to 30 psi....31-32 at the max. I was doing this when the car was warm, if it at all makes a difference...
I dont know if this has any part to do with it, but I also noticed what sounded like a vacuum leak coming from the EGR valve... I'm not positive that it is in fact the EGR valve, but it is coming in the general direction from under the runners.

If it is in fact a leak, could this be whats causing my fuel pressure to remain so low? I figured I'm going to tear the top end off this weekend but would like some ideas as to what the problems could be. Thanks

 

ttt

 

BAK,

Presuming you have the TPI, the minimum fuel pressure should be 37 PSIG ±3 PSIG for factory injectors. Your pump should be able to develop at least 48 PSIG with the engine running and the regulator vacuum line removed. Most can do 60 with no problem.

Low intake vacuum will not affect the fuel pressure of an electric pump. I'd start checking the fuel filter and regulator again, and perform a pressure and flow test on the pump.