The fuel pump is the auto part that brings gasoline from the fuel tank to the engine so that it can be combusted and you can drive your car around. When the fuel pump stops working, no gas can get to the engine, and you will not be able to start your car, let alone drive it.

Most newer vehicles use electric fuel pumps that are located in the fuel tank to supply the correct amount of fuel pressure to the fuel injectors. Older cars and trucks will have mechanical pumps on the engine block, while some vehicles use a dual-pump system where the tank is exceptionally far from the engine, such as in a pickup truck or an SUV.

When an electrical fuel pump malfunctions, the relay or the fuse will blow and the engine will stall, similar to running out of gas. If you know there is gasoline in the tank, you can bet that the fuel pump is the likely culprit for the dead engine. However, it could also just be a wiring issue, in which case you might not need to replace the pump.

If you suspect that the fuel pump is acting up, there are a few ways to test it out - and since you will be dealing with gasoline, it is important to work in a well-ventilated area.

First, you can remove the gas cap and listen closely as an assistant turns the key in the ignition to the ON position. If you do not hear a brief vibration, the next step is to turn the car off again and check the pump's fuse. The fuse panel is usually located under the dash on the driver's side and can either be opened manually or with a screwdriver.

The owner's manual of your vehicle will contain a guide to the fuses. Locate the one that belongs to the fuel pump and pull it out. Inspect it to see if the rod inside has been broken or damaged and ensure that the contacts are clean and not corroded. If it's fine, put it back. If not, replace it. Then check again for the sound. You should also pop the hood and check the fuel lines, hoses and connectors for any signs of damage or leaks.

Next, it's time to check the electrical components, which will require a voltmeter. Locate the fuel pump relay, which is often at the front of the engine in a cluster of relays or under the dash. Remove it and attach the voltmeter to the connectors. Have your faithful assistant once more turn the ignition on. If it measures no voltage, there could be a wiring problem between the relay and the fuse. You can further test this jumping the relay connectors to give the fuel pump some juice, and then go back to the gas cap to listen for that vibrating sound. If it works, a relay replacement should get things back in working order. If not, it's time to test the voltage of the pump itself.

The fuel pump connector can be found at the rear of most cars. Check the connections for signs of damage and corrosion before attaching the voltmeter. Then have your assistant do the same job he's been doing all day. The same rule applies here as it did for the relay connectors. If there is no voltage reading, the wires between the pump and the relay could be the source of the trouble.

The final test is to apply power directly to the pump with a car battery and some jumper cables. If you can't get it working, it probably needs to be replaced.