put the fuel pressure gauge on the car. with the key in the ON position, car off. the fuel pressure went to 31. tried again, 31.

then while starting the car, it hovered between 35-31 and then once started it sat at 37 at idle.
while in park i tapped the gas and held for a sec, each time i did that the fuel pressure would drop down to 32-33. and that was only tapping the gas peddle.
i am going to go drive it right now and see what happens at WOT.

i have another thread going about my dyno that i did yesterday and my A/F was 15.1 across the board.
from what i have read on here lately is that if your fuel pressure is anything under 40 at idle then either the FP itself or the FPR is on its way out.
truth to that? suggestions as to if my FP is good or bad?

thanks for reading.
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edit
just got back from driving it.
cruising speed 38 psi
WOT drops down to 30-32 and bounces in between.

 

probably the fuel pump

what is the pressure at idle with the vac line off the regulator?

 

It supposed to be at 38 PSI, when you take the3 vacume line off (WOT) it supposed to go up to 46 PSI

 

Stock fuel pressure with the vacuum line off is 41 - 47 psi.

 

so do i take the vaccum line off and take it out for a drive?
is there any test at idle i can do with the vaccum line off the FPR?

 

i took the vaccum line off
started the car and it had 41. at one point it went to 44 real quick and then came back down.
tapped the gas, stayed the same.
taped it agian and it dropped down to 38 adn came back to 41

thoughts?

 

You don't want to drive around with the vacuum line off as it's designed to compensate for changes in load fuel requirements. You pull the vacuum line off at idle just to prove your fuel pressure regulator is performing correctly by keeping fuel pressure between 41 - 47 psi.

Here's Shoebox's troubleshooting guide: http://shbox.com/1/4th_gen_tech2.htm...essure_testing

 

ok with vaccum line on, key ON. fuel pressure is at 36-37
with car at idle it stays the same at 36-37
then car idling pull vaccum off it goes to 44
plug hose back in, goes back to 36
hose off back to 44

so with that info and at WOT (31-32) is it safe to say my fuel pump is on its way out?

thanks again

 

Your idle fuel pressures are fine, showing that you're fuel pressure regulator is performing properly. You could have a clogged fuel filter that won't allow the fuel system to keep up with fuel demands at WOT.

Here's Shoebox's fuel system troubleshooting guide:
http://shbox.com/1/4th_gen_tech2.htm...essure_testing

 

i replaced the fuel filter in the last 2 months.
well i dont have an adapter and would rather not pinch a line and have problems in the future due to that.
i beleive it is my pump that is bad. i will be ordering one in the morning.
thanks again OBE