fuel pressure problems

[usp55]

ok so month back i was having very very hard starts and couldnt hold fuel pressure. was like that for ever but then i changed the fuel pump and that fixed everything, car stated right up every time for the better part of 4 months since. Now the past few days i started having hard starts again...wtf. also a less that perfect idle. A little low and slightly erratic at times.

I hear the pump prime just fine, pressure goes up and started to drop just like that. So i thought maybe the fuel pressure regulator went bad. pull that off (managed to snap a screw in half - ****) look at it and the diaphragm looks fine, no holes no nothing. either my check valve went again on the new pump after only maybe 5k miles. or what - leaking injector? The engine was rebuilt just over 30k ago. i would hope an injector would make it longer than that. Now i have been running a higher psi via an adj FPR but not much higher and only cause of the cam in the car.


any ideas?

[fredbmxer4life]

Re: fuel pressure problems

Put a new fuel filter following new fuel pump?

[usp55]

Re: fuel pressure problems

filter was right before the pump,

[ssms5411]

Re: fuel pressure problems

I think your fuel line hose came loose inside the tank, mine did after my install about 2 months later. My PSI gauge would show 40 PSi ,35 PSi then 30 PSI and would start to die. So I would check the pump again, hope you did the panel on the hatch.

[fredbmxer4life]

Re: fuel pressure problems

Well if you didnt put a hatch i would go ahead and replace regulator wont hurt after doing pump so you know they are replaced hand in hand. They dont run too much i replaced mine when i redid motor while i had fuel rail off look around a bit can find one for decent price. Just be glad you didnt burn up cat i did when my pump was going bad ran it lean to long i put new fuel pump in all happy going down road two miles later was having it towed back to bay at school garage pretty upset...

[usp55]

Re: fuel pressure problems

well the holly AFPR was about 115 and i pulled it off and it looks new, only a year maybe a year and a half old.

coming over the bridge today i had my window down for the tolls and i had theis strange noise - gota track that noise down. on my driverside of the car, a high pitched fast rattle. almost like a small exhaust leak but not.

Im gona pull the hatch pannel and start looking at the pump.

Also where is the fuel return line to the tank from the regulator - i only see the vacum line, but i know there has to be a return line - just dont see it.

[3.4grapeofwrath]

Re: fuel pressure problems

The fuel return line is connected to the rear of the fuel rail. You might want to check the fuel relay also located behind the drivers side kick panel. I had a fuel problem once and it turned out to be bad contacts on the fuel pump relay. The car will still run and drive but you won't get the proper voltage to the pump.

[usp55]

Re: fuel pressure problems

ok so basically have to reach back there and feel for it, i hate how this engine is so hard to work on.

its funny u mention the relay itself, the pump didnt prime everytime i turnd the key, starnge. but still the relay itself wouldnt cause my pressure to drop off like that, it should still hold. Where is the relay?