Fuel pump not priming...
#1
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Car has been hard to start lately, sometimes it starts for 1-2 sec then shuts off. Then I try again and it will start and runs fine, no hesitation or anything. I dont hear the pump come on at all when I turn the key, I used to hear it very clearly running for 2-3 seconds. I have a Walbro 255 lph pump, less thank 5k on it and I changed the fuel filter today thinking that could be it, didnt help. Then I checked for fuel pressure and I had 0 with key on, engine off. Once it started though I had 40 psi and the car will run and accelerate perfectly. What would cause the car to run perfect after started but not activate the fuel pump before starting? I've recently relocated the battery to the spare tire well, Im wondering if the fuel pump isnt getting enough voltage before startup. Or would a bad fuel pump relay cause this issue? Any ideas? Thanks.
#3
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If this happens Key ON Engine OFF, then it could be a relay issue (if it's intermittent, then it might be something more difficult). Swap the relay with another one, then try again, that's a quick test.
#4
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Swap Relay. Then check your wiring. Something sounds fishy. Also, recheck your grounds. I would invest in a multimeter at this point if you haven't already. When you moved the battery, did you redo your chassis/body grounds? Could be loose.
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Bought a multimeter and a new relay at autozone today. I really should have bought a multimeter years ago, about time I got one. Checked the voltage at the fuel pump relay circuit, right at 12v. Installed new relay and pump came on like normal when I turned the key and fired right up. Problem solved. They sure put that relay in a strange spot, I looked for it in the fuse panel inside the driver door, then with the other relays in the fuse box underhood. Finally looked it up in the manual and found where it was, behind the kickpanel to the left of the pedals. Of course, what better place to locate a single relay?
Also found it pretty funny that a decent auto multimeter cost $25 but the little fuel pump relay is $35, yeah that sounds about right, lol... Thanks for the help guys.
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#7
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Installed new relay and pump came on like normal when I turned the key and fired right up. Problem solved. They sure put that relay in a strange spot, I looked for it in the fuse panel inside the driver door, then with the other relays in the fuse box underhood. Finally looked it up in the manual and found where it was, behind the kickpanel to the left of the pedals. Thanks for the help guys.
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#10
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When you remove the glove box, all you can see is the tail end of a plastic tab which holds the VATS relay mounting bracket - FUN!!!
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Lol , that makes accessing the fuel pump relay seem like a piece of cake. I don't get it, why are these relays scattered and hidden through out the car? Seems like there was room for more in the underhood box? Who knows....