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-   -   Fuel pump issues (https://www.nopistons.com/2nd-generation-specific-17/fuel-pump-issues-73301/)

linchpin360 10-19-2009 12:30 PM

My fuel pump will not turn on after swapping to my V-Mount. The pump is a brand new walbro 255hp that has literally 10 seconds of run time on it. It worked before the swap. I have power at the ENGINE fuse and relay under the dash. I've tried 2 different resistor relays and still nothing. I'm to the point where I'm about to just wire it and run a toggle switch. Any Ideas? I have not yet tested for power at the resistor relay, but will be soon.

linchpin360 10-19-2009 01:06 PM


Originally Posted by linchpin360 (Post 834997)
My fuel pump will not turn on after swapping to my V-Mount. The pump is a brand new walbro 255hp that has literally 10 seconds of run time on it. It worked before the swap. I have power at the ENGINE fuse and relay under the dash. I've tried 2 different resistor relays and still nothing. I'm to the point where I'm about to just wire it and run a toggle switch. Any Ideas? I have not yet tested for power at the resistor relay, but will be soon.



I have check for power at the resistor relay and......... no dice. Where in between the circuit opening relay and the resistor relay could be the problem?

linchpin360 10-19-2009 11:35 PM


Originally Posted by linchpin360 (Post 834998)
I have check for power at the resistor relay and......... no dice. Where in between the circuit opening relay and the resistor relay could be the problem?



I was checking the wrong side of the circuit opening relay. I was checking the power coming in, not out. Its the relay.

linchpin360 10-21-2009 12:14 AM

ok. I'm running a hotwire. on the harness coming from the pump through the plate, which of the 4 wires is for power to the pump?

Firstgoodolboy 10-23-2009 11:25 PM


Originally Posted by linchpin360 (Post 835064)
ok. I'm running a hotwire. on the harness coming from the pump through the plate, which of the 4 wires is for power to the pump?





According to my diagram, the connector at the pump pin "C" should be the hot lead to the pump and should be blue, the "A" pin should go to body ground. Double check with a volt/ohm meter to be sure. It might be a good idea to check the incoming lead from the fuel pump resistor relay (either pin B or F at the relay). Check pin C for power (Disconnect the resistor relay and apply power to pin B or F at that connector, and check for power at the pump connector). It should be hot. Next disconnect the battery, check pin A at the connector closest to the fuel pump for body ground with an ohm meter - checks for good ground. Check the color of the two wires (A and C). Splice your switched hotwire into the pin C wire anywhere between the pump connector and the resistor relay where it's most convenient for you. Your pump should work. Good luck.

linchpin360 10-24-2009 02:06 AM


Originally Posted by Firstgoodolboy (Post 835165)
According to my diagram, the connector at the pump pin "C" should be the hot lead to the pump and should be blue, the "A" pin should go to body ground. Double check with a volt/ohm meter to be sure. It might be a good idea to check the incoming lead from the fuel pump resistor relay (either pin B or F at the relay). Check pin C for power (Disconnect the resistor relay and apply power to pin B or F at that connector, and check for power at the pump connector). It should be hot. Next disconnect the battery, check pin A at the connector closest to the fuel pump for body ground with an ohm meter - checks for good ground. Check the color of the two wires (A and C). Splice your switched hotwire into the pin C wire anywhere between the pump connector and the resistor relay where it's most convenient for you. Your pump should work. Good luck.



I have it running now. I took the power in for the circuit opening relay (B/W) and the power out (Bl/R) and spliced them together. This just bypasses the Circuit opening relay but still utilizes the resistor relay. It starts up first try and runs ok so far. I still need to change my TPS and find out why I have practically no vacuum. After that it should be all smooth sailing. Thanks for the info!


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