Low fuel pressure?
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Low fuel pressure? I just got the car in on a trade 98 z28, He told be about the fuel pressure being at 30#, but I have not put a gauge on it yet I just got the car last night. When you are driving the car and give it a lil gas it spits and sputters, also when you start it back up after it sits for a while it is hard to start, he told me that they guy he got it from had replaced the pump a lil while back, So it acts like it is leaking down would a hoe in the line going to the fuel pump in the tank do this, it has a walbro 255 in it, or could it be the Fuel press reg in the tank. Pls help.
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Yeah, you can replace just the regulator. You can get them at auto parts stores or a dealer. The only really bad part is that the regulator is in the tank, the regulator looking thing on the fuel rail is just a pulse dampener.
Hope that helps.
Hope that helps.
Last edited by SlonomaZ28; Nov 4, 2010 at 05:47 PM.
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Yep I know the Reg is in the tank.
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I put a fuel gauge, on it yesterday and when I cycle the key it goes up to 40psi and then falls fast to 0, so that tells me that the check valve in the pump in shot, or there is a hole in the rubber hose going from the pump. When car is running it only making 40psi. Is there anything else I should check out?
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Verdad Gallardo I put a fuel gauge, on it yesterday and when I cycle the key it goes up to 40psi and then falls fast to 0, so that tells me that the check valve in the pump in shot, or there is a hole in the rubber hose going from the pump. When car is running it only making 40psi. Is there anything else I should check out?
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Hey i have the same exact problem as you. been through 3 different pumps and still after a few days, the car is hard to start and sluggish when you give it gas. i have the tank down and pump out right now and i can see the baby blue o ring coming out of the regulater. to me it seems as though the metal piece holding the reg. on is too tight and makes the housing part oval shaped and eventually the o ring comes out and leaks..how bout spreading the retainer and putting some silicone around the seam?
I've had this issue 3 times now as well, and I don't think it's the clip. I'd look at all your fuel lines and make sure nothing's kinked anywhere. The soft lines aren't very long, and I believe it's caused by a kink in the return line.
EDIT: I was wondering about the silicone thing too. If anyone tries it, please post results.
EDIT: I was wondering about the silicone thing too. If anyone tries it, please post results.
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well ive done some testing today. i tried a couple diff setups. i tried putting 2 o-rings on at once and used a hose clamp and tightened the regulator down into its housing. this worked for awhile. im gonna try some more setups tommorow.
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think ive got the winning solution. The factory o-ring on the in tank fuel pressure regulators are kinda small. I went to the local parts store, picked up a thicker, tighter fitting o-ring, and put it on, AND put the stock o-ring on over the little black spacer. i put it all back in the regulator housing. tightened it all down and put a hose clamp over it the hole thing and tightened it on pretty good. Have romped on the car all day now and the o-ring hasnt popped of yet. And honestly i dont see how it can pop off with the thicker over sized o-ring. HOPE THIS HELPS
think ive got the winning solution. The factory o-ring on the in tank fuel pressure regulators are kinda small. I went to the local parts store, picked up a thicker, tighter fitting o-ring, and put it on, AND put the stock o-ring on over the little black spacer. i put it all back in the regulator housing. tightened it all down and put a hose clamp over it the hole thing and tightened it on pretty good. Have romped on the car all day now and the o-ring hasnt popped of yet. And honestly i dont see how it can pop off with the thicker over sized o-ring. HOPE THIS HELPS
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The reason the stock o-rings pop off is because the regulator housing gets oval shaped after awhile from the clip and snap ring pressing on it constantly. GM should have made that housing anything except plastic. So everytime you put the o-ring back on, it will eventually pop off because the housing is no longer circular. But with the bigger o-ring it creates a better and much tighter fit and seal. And on top of this i took the stock o-ring and placed it on the plastic spacer so I now have 2 o-rings. Once i got the o-rings and regulator to fit firmly down in the housing, I used a hose clamp to put around the housing and regulator and tightened it down just to assure this problem wouldnt happen again. I agree, you cant tell anything after one day, but my stock setup and o-ring would pop off usually once every hour or so. I have driven the car for about 12 hours today and gave her some hell and it has not popped off. Only time will tell. I do recomend you try this setup. I only cost 10 cents for an o-ring and a buck for a hose clamp.