How to Troubleshoot Fuel Pump Problemsby Contributor
The fuel pump is a key component of your vehicle. It pumps fuel from the gas tank to the carburetor or fuel injection system. If it isn't working properly, neither is your vehicle. Often, if dirt or rust particles enter the fuel line, those can clog the fuel pump's filter. Vehicles with 100,000+ miles tend to have fuel pump problems due to age, and you will need a pump replacement at some point. Another thing to watch out for is letting your gas level get too low. This can affect the lifespan of your fuel pump, since gas is required for cooling in some models.
Maintain your fuel filter according to your owner's manual. A clogged fuel pump filter is a common cause of trouble. If your car sputters at high speeds, or won't start at all, you may need to replace the filter, which is generally located right before or after your fuel pump, sometimes both. If it looks clean and you have replaced it at the recommended time, you may have a leak as opposed to a clogged filter.
Check the gas cap for leaks, then remove it. Be sure you also look at the gas tank and fuel lines leading from the tank to the engine to rule out leaks there. Use your nose. Gas has a distinct odor, and you can sometimes sniff out the source of a leak.
Turn the ignition key to the last click before starting your car. You may need to use a friend for this part. The idea is to listen at your gas tank for the fuel pump to kick on. Most of today's cars have the fuel pump inside the gas tank. When the gas cap is off, you should hear a humming sound for a few seconds coming from inside. If you don't hear anything, it's a safe bet that the fuel pump is not kicking on.
Locate the fuse box if your fuel pump didn't turn on. It is often located under the dash on the driver side or passenger side. A burned-out fuse could be the culprit. If the fuse for the pump is blown, replacing it should fix your problem. If not, you will need to access your fuel pump to manually check it.
Take off the gas tank's access panel if you are lucky enough to have one. This will let you get at the fuel pump without removing the gas tank. Otherwise, drop the tank so you can reach the fuel pump.
Find the fuel pump's electrical connector and check the voltage. Also make sure the pump is grounded. If both measurements are normal, but your fuel pump still isn't turning on, the pump is likely broken and will need to be replaced.