Fuel pressure too high when engine is running??

[s13_240_rb20]

I have an adjustable FPR on my RB20. I set the fuel pressure when the engine is not running to 37psi. Yet when I crank up the engine, the fuel pressure jumps up to 65 psi and sometimes even higher.

With the vacuum line attached the fuel pressure rises with throttle as expected. With it disconnected, the fuel pressure remains steady during throttle. I just got my alternator working and it charges at 15v when the engine is running...is that too high and does it affect fuel pump performance??

Is there supposed to be such a drastic difference in fuel pressure when the engine is running and not running?? or is this normal? I don't recall this drastic difference when the engine was in my 240sx.

--TJ

[PorkChopExpress]

why are you setting the fuel pressure when the engine is off? how are you even doing that? hot wired the fuel pump? turn the motor on, un plug the vacuum line, set it and get back to us with the results.

the fuel pressure should stay the same until it receives manifold pressure.

[s13_240_rb20]

why are you setting the fuel pressure when the engine is off? how are you even doing that? hot wired the fuel pump? turn the motor on, un plug the vacuum line, set it and get back to us with the results.

the fuel pressure should stay the same until it receives manifold pressure.

Ya, I have a hotwired fuel pump to a switch. I'll try that in a couple of minutes when I go out back and put on my hood pins.

It also happens to make weak power when driving, but it revs greaaattt in neutral...gotta look into that too...

--TJ