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Q: No power to fuel pump

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I thought my fuel pump had died, so I replaced it. My car still won't start. I then checked the wires for power using a test light and could detect no power. I checked the fuel power relay on the firewall and all four wires had power.

A: Sounds like you might have an electrical is...

Sounds like you might have an electrical issue. If all 4 wires on the relay had power, there is something wrong with the wiring. The relay wires should have ground on two wires, power on one wire and switched power on another wire. To activate the fuel pump the computer actually connects one of the ground wires to complete the circuit and send power to the fuel pump. The wire coming from the fuel pump is the other ground wire. Electrical wiring issues can be a nightmare if you don’t have the appropriate wiring diagrams to see which wires go to where. A mechanic, such as one from YourMechanic, will have access to the proper schematics to help you diagnose this your fuel pump’s loss of power and have your car safely back on the road.

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