fuel pressure
fuel pressure
Ok, A couple of day ago I had some issues with my fuel pump. so I rewired it and got it to run. after that, the fuel pressure wouldn't hold after I cut the car off. It would drop straight to 0 psi. So, I replaced the FPR with another one that I had in my garage. It seemed to work fine. Yesterday I noticed that the pressure would bleed off to 0 psi after about 1 hour, I didn't try to do anything about till today. Well today I started to look at it and NOW when I start the car the fuel pressure is a little low while running. The FPR responds the vac, but when I cut the car off the fuel pressure will drop to about 25 psi and then slowly go UP yes UP not down. it goes up to about 45 psi and holds there. Its been sitting in my garage for about an hour and it hasn't dropped yet. Could that be another bad FPR or is something wrong with the pump? also when I open my gas tank it doesn't have any pressure in it like it did before.
Re: fuel pressure (esahuque)
Sounds like you have a screwy gage dude. There is no way your fuel pressure should go up after power is cut from the pump unless you have it wired to run when the car is off.
Other than that, it might be the check valve on your fuel pump. Sometimes those will fail and they wont hold fuel pressure against the pump.
Other than that, it might be the check valve on your fuel pump. Sometimes those will fail and they wont hold fuel pressure against the pump.
Re: fuel pressure (480sx)
well, I did some more testing and it seems the the 2nd FPR I put on is not holding pressure properly either. the fuel pressure is not holding steady, its at different psi each time i start it. and it leaks out sometimes and sometimes it holds after I cut the car off. I ordered a nismo FPR, hope that clears it up
Re: fuel pressure (esahuque)
You sure you dont have a fuel rail leak? Other than that the FPR or the pump is all thats left.
Re: fuel pressure (480sx)
I pulled my rail and and primed the system to checked the injectors for leaks, I have an in-line gage right after my filter and if i clamped the line before the gage and the pressure goes down. If i clamp the line after the fpr it doesn't go down. since i pulled the fuel pump, I also check the clamps at the pump cover, the pressure line clamp was a little weak so I replaced that one. the only thing left is the fpr, so I bought a nismo one. I will be installing it this week end.