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Never-ending Fuel system problems

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Old Dec 18, 2005 | 01:19 PM
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Default Never-ending Fuel system problems

Ok so i finally got time to work on the truck again today. A little background for those that dont remember.
-1999 f-body fuel pump assy with the fuel pressure regulator removed
-97-98 vette style return fuel rail setup with in rail fuel regulator
-I have two 3/8" lines running the length of the frame connecting to the fuel rails---pretty straightforward.

For some reason when I have the lines hooked up the way pictured, which I believe is the proper way the injectors dont get any fuel. If I push the shrader valve in there is no fuel at all coming out. When I switch the fuel lines around it starts and runs fine.


Last time I posted with this problem I was told to remove the regulator on the fuel pump assembly, so I tried it and it didnt seem to affect anything.

Is it possible the rail mounted fpr is defective? I was told this was all new from S&P when I bought the package.

If no one else has any ideas will it hurt to run the fuel lines "backwards"?

thanks guys...this is just one of those things that just I cant seem to fix myself so I appreciate the help!
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Old Dec 18, 2005 | 02:32 PM
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Are you sure the fuel pump isn't wired backwards?
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Old Dec 18, 2005 | 02:50 PM
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Agreed with 70, check your wiring and make sure it isn't backwards for some reason.
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Old Dec 18, 2005 | 03:51 PM
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that is something that never crossed my mind....so if I have the power and ground swapped that would mean the pump would be pumping in reverse?
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Old Dec 18, 2005 | 04:01 PM
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It might. It's worth looking into.
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Old Dec 18, 2005 | 04:21 PM
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I just looked at a 99 spare pump & the pump is hooked to
lower line & top line is return. Good luck Dale
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Old Dec 18, 2005 | 04:39 PM
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ok on the 4 wire plug on the fuel pump I have the black wire (C) going ground and the gray one (B) running to the power source. I cant seem to find the wiring diagram for this (search isnt working right now). Should I just swap them around and see what happens?
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Old Dec 18, 2005 | 05:02 PM
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Leave the wiring alone and fix the plumbing first.

If you have the picture labeled correctly you have those lines swapped. The line out of the FPR is the return line NOT the feed line.

And yes the FPR needs to be removed from the tank unit when using a fuel rail FPR. I hope you didn't put it back in.

Quote: "When I switch the fuel lines around it starts and runs fine."
That ought to tell you something.
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Old Dec 18, 2005 | 05:22 PM
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Originally Posted by Speartech
Leave the wiring alone and fix the plumbing first.

If you have the picture labeled correctly you have those lines swapped. The line out of the FPR is the return line NOT the feed line.

And yes the FPR needs to be removed from the tank unit when using a fuel rail FPR. I hope you didn't put it back in.

Quote: "When I switch the fuel lines around it starts and runs fine."
That ought to tell you something.
lol i feel like an idiot....so i had it the right way in the begining a couple months ago. I should have just stuck with my instinct on that one. Anyways, I took the tank mounted FPR out like you suggested a few months ago and left it out. So I will go ahead and swap the lines once more and call it good.
Just a matter of sealing up those darn Russell Aluminum compression fittings now.

thanks for the help everyone
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