I can hear fuel pump run but no pressure
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Car: '87 Pontiac Firebird
Engine: 2.8 V6
Transmission: Auto
I can hear fuel pump run but no pressure
Hello all, I need more info before I change the fuel pump. My car won't start, I have a FP tester gauge and when I test the pressure the needle on my gauge barely moves, like 2 psi, I know it should read 40 something, any way. I can hear the relay click and I hear the fuel pump buzzing and running when I turn the key on but No pressure. Is there anything else I can check before I invest in a new fuel pump or is it worn out? Any help would be great. Thanks
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Re: I can hear fuel pump run but no pressure
If the fuel line connection from the pump to the inlet line is faulty the pump can run great but be of no help. Unfortunately the only way to find out is taking it all apart, and by the time you've done that, only replacing the hose and not the pump would seem foolish. Don't know of any other way, but there's lots of smarter folks on here than me. Good luck!
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Car: '87 Pontiac Firebird
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Re: I can hear fuel pump run but no pressure
well, I had a friend replace the fuel filter so it's New, maybe he installed it backwards? is that possible? I did read some thing about the fuel pressure regulator might be worn and it could send all the fuel back to the tank, so the pump wouldn't hold pressure is that right?
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Re: I can hear fuel pump run but no pressure
I'd make sure fuel filter was on correctly - should have an arrow pointing to the front of car.
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Re: I can hear fuel pump run but no pressure
If the fuel line connection from the pump to the inlet line is faulty the pump can run great but be of no help. Unfortunately the only way to find out is taking it all apart, and by the time you've done that, only replacing the hose and not the pump would seem foolish. Don't know of any other way, but there's lots of smarter folks on here than me. Good luck!
i have seen this happen many times . after 20+ yrs. soaked in fuel the rubber/flex house leaks like sieve . good luck .
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Re: I can hear fuel pump run but no pressure
Ok here is what I recommend for whats is worth
Check pressure straight from the pump before the filter. This way you know the pump is for sure working.
If the pump is working then work your way up the fuel system until you no long have fuel pressure.
Just because the item is new does not mean it works. Sometimes we get lemons with new items.
Also just because you hear the pump does not mean it is working. Something internal of the pump could be damaged but the motor still runs.
Think of it like this if you have a vacuum cleaner running and the hose has a big hole in the side of it. You hear the motor but no suction. The internal pump could be running but has a defect internally causing no fuel to be dispensed..
Hope this helps you get going again.
Check pressure straight from the pump before the filter. This way you know the pump is for sure working.
If the pump is working then work your way up the fuel system until you no long have fuel pressure.
Just because the item is new does not mean it works. Sometimes we get lemons with new items.
Also just because you hear the pump does not mean it is working. Something internal of the pump could be damaged but the motor still runs.
Think of it like this if you have a vacuum cleaner running and the hose has a big hole in the side of it. You hear the motor but no suction. The internal pump could be running but has a defect internally causing no fuel to be dispensed..
Hope this helps you get going again.
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Car: '87 Pontiac Firebird
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Re: I can hear fuel pump run but no pressure
OK thanks for all your info. will check things out and let you know what I find. thanks again....
#10
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Re: I can hear fuel pump run but no pressure
I am experiencing a similar problem right now. Car was sitting for years, was started up regularly but eventually it would not start at all as it was not getting fuel. New fuel pump and filter installed (original fuel pump was not replaced, and the new fuel pump installed under the bonnet) by mechanic. After this was done the car was running, but intermittently stalls out and continue to stall. I believe the fuel line still runs through the old fuel pump and that the old fuel pump may be getting blocked and has been slowly deteriorating. Next step is to remove the fuel tank and completely flush it out to ensure there is no old fuel or mucky/grime (what ever you want to call it) stuff still floating around in the system and remove the old fuel pump which is at the top of the fuel tank. . (My car was converted to a 350 Chevy before I purchased and was using the original fuel pump). Removing and flushing the fuel tank will happen next week.
#12
Re: I can hear fuel pump run but no pressure
I am experiencing a similar problem right now. Car was sitting for years, was started up regularly but eventually it would not start at all as it was not getting fuel. New fuel pump and filter installed (original fuel pump was not replaced, and the new fuel pump installed under the bonnet) by mechanic. After this was done the car was running, but intermittently stalls out and continue to stall. I believe the fuel line still runs through the old fuel pump and that the old fuel pump may be getting blocked and has been slowly deteriorating. Next step is to remove the fuel tank and completely flush it out to ensure there is no old fuel or mucky/grime (what ever you want to call it) stuff still floating around in the system and remove the old fuel pump which is at the top of the fuel tank. . (My car was converted to a 350 Chevy before I purchased and was using the original fuel pump). Removing and flushing the fuel tank will happen next week.
Probably not your exact issue, since you said you replaced the fuel pump, but perhaps there is a check valve somewhere else in your system (they can be built into some fuel filters as well). It's possible for a tank to get so gunked up that the sock doesn't pass gas anymore, but that's a lot of crude!
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