What should the voltage be on a fuel pump?
Also test the output terminal of the fuel pump to see if it is functioning as expected. If the voltage drop is greater than the recommended reading of 0.1 volts then this is a confirmation that indeed the harness connectors or the wiring is faulty. You need to locate the exact location of the fault to correct the problem.
What happens when you lose 4.0 volts on a fuel pump?
The loss of 4.0 volts may not affect the idle of a vehicle, as the fuel pressure may be within specifications. But, when more volume is required, as when the vehicle is under acceleration, it could be starved for fuel. It doesn’t take much to introduce 0.5 ohms or more of resistance into an automotive electrical circuit.
Where does the power come from for a fuel pump?
Are you getting power from the E.F.I. (electronic fuel injection) relay to the fuel pump relay on the B (black) wire at the fuel pump relay base? The fuel pump relay will not pull in if the ECM is not taking the relay coil to ground to complete the circuit.
What kind of wire to run fuel pump?
You can run a wire from the (power) red side on the battery to the fuel pump gray wire and a ground to the frame to test the pump and wiring issue. Just a thought.
Also test the output terminal of the fuel pump to see if it is functioning as expected. If the voltage drop is greater than the recommended reading of 0.1 volts then this is a confirmation that indeed the harness connectors or the wiring is faulty. You need to locate the exact location of the fault to correct the problem.
The loss of 4.0 volts may not affect the idle of a vehicle, as the fuel pressure may be within specifications. But, when more volume is required, as when the vehicle is under acceleration, it could be starved for fuel. It doesn’t take much to introduce 0.5 ohms or more of resistance into an automotive electrical circuit.
Are you getting power from the E.F.I. (electronic fuel injection) relay to the fuel pump relay on the B (black) wire at the fuel pump relay base? The fuel pump relay will not pull in if the ECM is not taking the relay coil to ground to complete the circuit.
How can I tell if my fuel pump is working?
Insert the key into the ignition and turn on the key without starting the engine. A soft whirl sound should come from the pump indicating that it is ready to pump fuel into the engine. If the pump is functioning, find out if it is receiving enough electrical power.