Often, it’s not the pump itself that fails to function but the power that supplies it. Check your owner’s manual for the location of the fuse box, then find the fuse that corresponds to the fuel pump. After that, you should pull it out and examine if there are any signs of failure. If the fuse is blown, it will be broken or burned. If it looks good, check the rest of the fuses related to the fuel system for signs of being blown and replace them, if necessary. If no fuses are blown, have a helper turn the key while you listen for the fuel pump relay clicking on.

Just because you’re getting juice from the circuit doesn’t mean that it’s getting to the pump itself, which makes it important to check the voltage there as well. Check out your vehicle’s service manual to find out where to check and the proper procedure for checking it—test for source voltage to determine whether the good charge leaving the fuse is getting to the pump. If there is not enough power to pump fuel, then you should check the electric fuel pump relay circuit. You could have a bad relay.

Fuel is supplied from a low-pressure electric lift pump mounted in the fuel tank to a high-pressure fuel pump mounted on the back of the engine. As a result, the high-pressure electric fuel pump provides pressurised fuel to the injectors along the route. 

A pulley mechanically drives the HP fuel pump on the end of the left-hand exhaust camshaft via a toothed drive belt (remember these are twin-cam cylinder heads, each having a camshaft for the inlet valves and one for the exhaust valves). The automatic sprung tensioner pulley sustains the drive belt tension, and it is this tensioner pully, and the belts need to be replaced. 

Have an assistant crank the engine while you hit the fuel tank with a rubber mallet. If the vehicle starts during this technique, it is clear that the pump inside the electric vehicle is not in good condition. Whacking the tank jars the motor enough to get things going – but only temporarily.

Be warned: this procedure can cause personal injury, as well as damage to your engine. Try it at your own risk with the proper safety equipment, such as a fire extinguisher, on hand. Before you do this, you should be wearing your safety glasses and a  protective suit. Do not use starter fluid on a diesel engine. If you decide to attempt the test, try to start the vehicle by removing the air intake and spraying starter fluid into the throttle body. Have an assistant crank the engine while you spray – if it starts and runs momentarily, the problem is fuel-related and may indicate a bad pump. You’ll want to check fuel pressure as your next step.

A pump may produce adequate pressure yet not create enough volume. And that’s where a fuel pump volume test comes in handy. Most of the time, you can use the fuel pressure gauge to evaluate the volume of the electric fuel pump. 

Start by connecting the gauge and placing the bleed end of its hose into a clean container. Without starting the engine, activate the pump for 15 seconds while you hold down the relief valve on the tool. Usually, the electric fuel pump should provide about a pint of fuel during that period. Consult the repair information for the exact procedure and specifications for your vehicle.

If you are a car owner, you must know the basics of how your vehicle’s engine works and some of its essential parts, like the electric fuel pump. Hopefully, after reading this article, you must now have already known more about the electric fuel pump than before. These pieces of information will be beneficial if you encounter future problems caused by a faulty electric fuel pump.