LS1 FPR Problem?

[Zero4488]

Has any one had experience with the fuel pressure regulator on the stock LS1 rails going bad? Is it even possible for it to go bad? I'm assuming it has a diaphragm like a regular vacuum regulated one but I really don't know how the stock LS1 regulator works....is it possible for it to be replaced or do I have to replace the complete rail setup? Any info on this would be terrific....

-Dave

[S.J.SLEEPER]

hey dave,
its Curt, Bills friend. What makes you think fpr is bad, and what year is your car?

98 only year to have fpr on rail. 99 & up has a frp'looking piece on the fuel rail, but it isn't a fpr, its a damper.

99 & up have the fpr in the tank on the fuel pump module.

if the fpr is bad in tank, fuel will bleed back into tank after key is off.

hook up fp gauge,cycle key foward,you'll see fp go to anywhere between 45&58 psi. turn key off, if fp drops 5-10 psi with in 2-3 minutes than pump/fpr may need replacment.
if it doesn't drop, than pump/fpr is good and you have another problem.

Rob's got my # so give me a ring if you need help.

[Zero4488]

Originally Posted by S.J.SLEEPER

hey dave,
its Curt, Bills friend. What makes you think fpr is bad, and what year is your car?

98 only year to have fpr on rail. 99 & up has a frp'looking piece on the fuel rail, but it isn't a fpr, its a damper.

99 & up have the fpr in the tank on the fuel pump module.

if the fpr is bad in tank, fuel will bleed back into tank after key is off.

hook up fp gauge,cycle key foward,you'll see fp go to anywhere between 45&58 psi. turn key off, if fp drops 5-10 psi with in 2-3 minutes than pump/fpr may need replacment.
if it doesn't drop, than pump/fpr is good and you have another problem.

Rob's got my # so give me a ring if you need help.

I learn something new everyday....but here's another question....when I originally had my nitrous kit on my car I had a fuel pressure gauge, and everytime I went WOT the fuel pressure went up....now when I put a fuel pressure gauge at WOT the fuel pressure drops....could this be part of my issue Curt? I've already checked if the fuel pressure drops with Bill....and it stays at like 50.....

[S.J.SLEEPER]

well, @ wot if the fp is dropping off sounds like your running out of fuel,(pump going bad/not strong enough for the fuel demand)
any changes since? bigger injectors? cam? heads? you might not have enuff pump to support mods or if stock than pump is on its way out the back door !!!

[Zero4488]

Originally Posted by S.J.SLEEPER

well, @ wot if the fp is dropping off sounds like your running out of fuel,(pump going bad/not strong enough for the fuel demand)
any changes since? bigger injectors? cam? heads? you might not have enuff pump to support mods or if stock than pump is on its way out the back door !!!

I had just put in the ractronix pump with the hotwire kit....and my car is still the stock setup it's been....I'm starting to think this is my breaking up issue I've been having....what do you think?

[S.J.SLEEPER]

make sure the hose from pump to module isn't kinked.
did you change your fuel filter jackass? lol

if your breaking up @ top like I remember you stating,then yes.... if running out of fuel(fp dropping) the cars running lean @ top which will cause a breaking up/popping/missing effect.

And for gods' sakes.....what is the POS turd gen in your sig doing there. Drop that thing off @ cosmos will ya !!!

[Zero4488]

Originally Posted by S.J.SLEEPER

make sure the hose from pump to module isn't kinked.
did you change your fuel filter jackass? lol

if your breaking up @ top like I remember you stating,then yes.... if running out of fuel(fp dropping) the cars running lean @ top which will cause a breaking up/popping/missing effect.

And for gods' sakes.....what is the POS turd gen in your sig doing there. Drop that thing off @ cosmos will ya !!!

That POS is my high school ride...I've had it for years....as far as the fuel filter it was changed not too long ago....and Bill and I did the pump....actually Bill did the pump while I hooked up the hotwire kit.....so I doubt he kinked it....any ideas on what it could be? Where is the regulator in the tank/pump assembly? Could that be replaced?

[S.J.SLEEPER]

regulator is mounted to the fuel pump housing, yes can be replaced or you can bypass it and run a external fpr

[Zero4488]

Originally Posted by S.J.SLEEPER

regulator is mounted to the fuel pump housing, yes can be replaced or you can bypass it and run a external fpr

I guess I'll look into replacing it cause I don't have the money to do a fuel system right now....