Okay so I recently picked up an interceptor gauge as well as an sct xcal2 tuner for the mustang. After stalling the interceptor I noticed that the fuel pressure went down to 25psi at around 4k RPM and at that exact point the duty cycle reading was 100%. I figured the gauge was messed up since I notice zero power difference or kicking at any point even at those ranges. I decided to do some datalogging with the sct and it turns out the gauge is correct and 25psi/100% were indeed accurate readings at 4k+. What I don't understand is my car is basically stock besides an intake and exhaust. I did some more logging today and found another thing interesting. I installed a stewart warner fuel pressure gauge and at idle it reads around 40psi and the fuel pressure tester i hooked up at the shrader valve read 40psi at idle as well so i know this is accurate. Problem is my interceptor reads 52psi at idle and when i data logged at idle it read 52psi as well. I have no idea where to start with this...please help me diagnose this weird issue.
BTW the car is a 2000 Mustang GT with ~78k miles.
BTW the car is a 2000 Mustang GT with ~78k miles.