fuel pump works but no fuel pressure

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DubsSuck
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fuel pump works but no fuel pressure

Postby DubsSuck » Sat Jul 16, 2011 8:31 am

ok so like the heading said the fuel pump works but there is no pressure through the lines... what are the possible reasons for this and what are ways to fix it?


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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Sat Jul 16, 2011 5:52 pm

Any ideas?

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Re: fuel pump works but no fuel pressure

Postby compactfean » Sat Jul 16, 2011 11:10 pm

Fuel lines backwards, fuel pressure regulator bad, fuel line from pump to pump cover bad or disconnected. All I can think of for now but that should be enough to check for now.

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Mon Jul 18, 2011 9:49 am

Well im not doinng a rebuild, soo the fule line isntt in backwards. But, I did get a chance to look at it, and the fuel line is rusted like hell. Im ggonna bet that its got some holes in it

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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Mon Jul 18, 2011 6:45 pm

i did change injectors 3 and 4... im not sure, but would i have to bleed the fuel rail after changing injectors?

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Re: fuel pump works but no fuel pressure

Postby big monkey racing » Mon Jul 18, 2011 10:52 pm

when was the last time your fuel filter was changed?

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Tue Jul 19, 2011 9:12 am

A Month ago

compactfean
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Re: fuel pump works but no fuel pressure

Postby compactfean » Tue Jul 19, 2011 3:46 pm

Pull the cover to the fuel pump. Have someone turn the key on and see if you have fuel spraying from a bad line but back into the tank. If fuel isnt leaking there or anywhere else than I'd say your fuel pressure regulator is bad. Disconnect the fuel line at the fpr and turn the key on. If it sprays fuel like a garden hose than the fpr is bad. If you don't get any fuel, than your pump is not strong enough to move any fuel, or you have a fuel leak somewhere.

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Wed Jul 20, 2011 9:30 am

Thanks ill check that out and let you know what happends

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Re: fuel pump works but no fuel pressure

Postby esd51918 » Thu Jul 21, 2011 6:09 pm

In regard to your question about bleedng the fuel rail, the answer is yes. If you have had the rail opened up such that the fuel has been drained out then the fuel system will have to be bled. I'm basing this on previous experience with my SOHC. I had the fuel rail off and the injectors out to have them reconditioned. I got the injectors back and put it back together. When I turned on the ignition I could hear the fuel pump power up but when I cranked the engine it didn't fire. I cranked it several times and still no fire. At this point I quit in disgust and went looking for a cold beer. The next day I tried cranking it again. After about the third crank the engine tried to fire. On the next attempt the engine finally caught. The engine was running rough but it was running. After a few seconds I could tell the engine was starting to smooth out. At this point it dawned on me that the fuel rail had been full of air. It was not until I had cranked the engine enough to get sufficient fuel in the cylinders that it would fire. The engine has run fine since. Some fuel rails have a bleeder valve on them. The SOHC rail doesn't but your engine might.

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Fri Jul 22, 2011 9:28 am

Oh yeah? I was looking for a thread to locate the bleeder valve but I couldn't come up with anything for a kade

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Re: fuel pump works but no fuel pressure

Postby biggie » Fri Jul 22, 2011 9:39 am

Never heard of bleeding the rail on a kade. With the open system going back with the return line it should bleed itself. I had no issue when swapping rails.

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Re: fuel pump works but no fuel pressure

Postby compactfean » Fri Jul 22, 2011 10:48 am

No bleeder valve. According to the fsm you pull the fuel pump fuse and start the car until it dies to relief all fuel pressure. Once any fuel related repairs have been done you must cycle the key and prime the fuel pump to push out any air and build fuel pressure. Once the fuel pump changes sounds when priming then car is ready to start. This is all normal.

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Fri Jul 22, 2011 10:31 pm

What if an Injector hasn't made a complete seal? would that not allow enough presure for fuel to Move throught the lines?

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Re: fuel pump works but no fuel pressure

Postby compactfean » Fri Jul 22, 2011 10:54 pm

Kind of....you would rather be dumping fuel into the motor and smoking from being so rich or the other injector seal would be pissing like a race horse out of the top...either way I can tell you that's probably not it. Have you checked anything I've recommended? Do you know what your fuel pressure is?

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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Sat Jul 23, 2011 6:33 am

Not yet ill be able to work on it today... that is if its not too hot

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Re: fuel pump works but no fuel pressure

Postby jaredta1a » Sat Jul 23, 2011 4:57 pm

keep it simple, treat it like an electrical fault, do you have fuel at the outlet at the pump nipple follow the line till you find the restriction, make sure your filter isnt backwards.

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DubsSuck
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Re: fuel pump works but no fuel pressure

Postby DubsSuck » Sun Jul 24, 2011 3:55 pm

Ok So I got the fule system primed and built up enough pressure to be able to hear it go pshhhooo when I take the gas cap off... so it has pressure. But when I have someone try to start it while my head is under the car right by the tank I can smell gas... but I don't see it spraying anywhere... no puddles no nothing. Soo I have a leak somewhere just not sure what or where. Also I didn't smell anything when my head was in the engine bay so its be hind the fuel filter.

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Re: fuel pump works but no fuel pressure

Postby Dxta » Sat Dec 26, 2020 12:50 pm

Did you finally fixed this problem?

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Re: fuel pump works but no fuel pressure

Postby NukeKS14 » Sat Dec 26, 2020 7:58 pm

Dxta wrote:
Sat Dec 26, 2020 12:50 pm
Did you finally fixed this problem?
This thread is 9 years old. guessing OP has moved on since then. Are you having a similar issue?


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