How to Replace a Gas Tank Sending Unit

Very often we take for granted the valuable service we receive from varied components in our vehicles. Take the gas tank sending unit for example. Its only job is to communicate with the fuel gauge on the instrument panel and let us know how much gas we have left in the tank. When the sending unit breaks down we practically begin driving on luck, and we might run out of it on our way to work, in the middle of the highway. However, in a matter of minutes you can replace the fuel sending unit and take the guesswork out of your driving.

Things You'll Need

• Jack and jack stands
• Pliers
• Screwdriver
• Hammer and drift punch
• New lock ring gasket

Instructions

1. Park the car in a safe place and locate the fuel tank--on some vehicle models the tank is mounted underneath the back seat; others are mounted on the underside of the car and provide access to the fuel pump and sending unit assembly through a small metal door screwed in the trunk, under the carpet; still on other vehicle models, the only access to the tank is from underneath the vehicle.

2. Open the hood and disconnect the black negative cable from the battery terminal.

3. Remove the back seat, the small access door in the trunk or lift the back of the car using a jack and safely support it on jack stands and lower the fuel tank.

4. Unplug the electrical connector and the fuel hoses from the fuel pump and sending unit flange on the tank using a pair of pliers or screwdriver.

5. Remove the cam lock that holds the pump and sending unit flange in place in the fuel tank. Use a screwdriver or drift punch and a hammer to turn the lock ring tabs counterclockwise until the assembly is free.

6. Lift the fuel pump and fuel level sending unit assembly off the tank carefully--discard the old lock ring gasket and replace it with a new one.

7. Unscrew the fuel sending unit off the fuel pump assembly and install the new one.

8. Install the new lock ring gasket, the pump and sending unit assembly and lock ring.

9. Connect the fuel hoses and electrical connector. Replace the back seat, access door in the trunk or lift and bolt the fuel tank back in place underneath the vehicle and lower the car.

10. Connect the negative cable to the battery terminal.

Tips & Warnings

• Consult your vehicle service manual to easily locate components. You can buy a service manual at most auto parts stores or consult one for free at your public library.

• Gasoline is highly flammable. Make sure you are working in a well ventilated area, away from appliances with open flames like dryers or water heaters and do not allow smoking near your vehicle.