No power to Fuel Pump or relay

thenderson2011

thenderson2011

New Member
Feb 11, 2012
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Caney, Kansas
I have done a head gasket replacement on this car and it's been sitting for a while, but when I try to start it, the fuel pump won't turn on unless I jump the b+ and fp on the diagnostic box. I get no power with a tester light at my relay or my fuel pump, and I'm now stumped as to what I should do. I have replaced the efi main fuse in the fuse box near the battery, but still no power.
 
hvyman

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
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Fullerton,CA
The fuel pump does not get turned on unless there is air flow. Check the afm.

Also there should be power up to the relay on the switch side. If there is not follow the wiring diagram and trace it back.

If efi fuse was blow nothing on the engine would get power ...
 
T

Trent

Quietly Browsing
Oct 30, 2007
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Austin TX
Search for a thread here that mentions bypassing the fuel pump relay. Its just a matter of putting a jumper wire on two of the terminals in the relay harness (passenger side inner fender, easy to get to). See if it will start after that. Mine did the same thing after sitting for a few years and I bypassed the relay and never a problem again. Started right up after that. I then took it a step further and did the full 12V mod to the pump on the Walbro to eliminate all that.
 
S.A. supra

S.A. supra

New Member
Feb 15, 2009
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Buda, Texas
Or just jump the fp with the b+ at the diagnostic box. Well that will just kick the fp on by bypassing all the relays. So that won't really help.

I'm having a problem similar to yours. My fuel pump will not kick on. But if I leave the key in the on position and then go to the fuse box next to the battery and thump it I can hear the fuel pump kick on. A buddy of mine suggested that it might have something to do with a bad ignition switch. I'm still working on that now.
 
T

Trent

Quietly Browsing
Oct 30, 2007
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Austin TX
Fuel pump shouldn't kick on when you turn the key to on. Pump should only be priming and turning on when you start the car. When you first turn the key you might hear it prime for a second or two, but that's it. It won't continue to run after that unless you start the car.

Bypassing the relay as I suggested will effectively verify if the relay is dead or not functioning and is a common thing to fail over time with these cars. Jumping the FP just tests your fuel system to make sure the pump works and that there aren't any leaks. Bypassing the relay will allow you to start the car and let it run like that for good if you want to. It's also a nearly free thing to try before you start replacing or trying to replace anything.
 
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