Fuel pump on constantly with ignition???
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From: Thomasboro, ILL
Fuel pump on constantly with ignition??? I installed a whole new fuel system this winter, and went to test the pump and when i turned the ignition on the pump just stayed on, and wouldnt go off. It used to prime for about 2 seconds then turn off. The pump is a Magnafuel 750 so i can easily hear it 
. I check all the wires and nothing has changed since last year. What would make the pcm want to prime then stay on, i thought it went off the crank sensor???
. I check all the wires and nothing has changed since last year. What would make the pcm want to prime then stay on, i thought it went off the crank sensor??? Thread Starter
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From: Thomasboro, ILL
Did you change relays? Change any wiring at all? If not, then I'd suspect it's a relay issue, as they trigger the pumps on/ off. I've never seen a relay go out due to non-use, but I guess it's possible. Try lightly tapping on them to see if the pump will turn off.
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I swapped it out with another and no difference. Is it possible the crank sensor is stuck?
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From: Thomasboro, ILL
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Double checked all the grounds firewall forward to make sure none were loose or off. I only have about 4 grounding spots as i redid my whole damned harness. One of them was loose, i grounded it and it worked. Didnt do much testing just making sure nothing was my fault first. This time happened to be human error.
Ah, well some jack asses I had doing some work to my car decided to hack the harness up. Now, the pump stays on. Guess I need to break out the schematics again. Love the build by the way.
