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Q: My gas gauge is doing a funny little dance.

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As I was driving along, my gas gauge began to rapidly and randomly jump between empty and full. I know the car has nearly a full tank, and sometimes the gauge would stop in empty,while other times it would say the tank was full. What could be going on?

My car has 180000 miles.
My car has an automatic transmission.

The fuel pumps are all inclusive on what they call a fuel module or assembly. These modules include a float (quite like the float on your toilet) that tells the computer and your dashboard where the fuel level is at.

The issue may be with the pump’s float, with the sensor on the float, the instrument cluster for your dash board, or the wiring between the two. If you have never replaced the fuel pump, it may be time. If the float is wearing down, the rest of the components are getting close. Are any other parts of the dashboard acting funny? If not, the pump is likely the culprit. Be sure to have a professional mechanic, such as one from YourMechanic, take a look and replace the fuel pump.

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