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Q: Fuel pump

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Less than 12 volts at fuelpump conection pump wont engage.

My car has 236000 miles.
My car has an automatic transmission.

This sounds like you may not have any power or intermittent power going to the fuel pump relay. The relay wires should have ground on two wires, power on one wire and switched power on another wire. To activate the fuel pump your ECU actually connects one of the ground wires to complete the circuit and send power to the fuel pump. If the wires all have power running through them, then it is likely you have a faulty relay. The wire coming from the fuel pump is the other ground wire. I would recommend having an expert from YourMechanic come to your location to diagnose your wiring as this can be very difficult and time consuming without the proper wiring diagram.

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