Q: The fuel gauge moves up and down I never know how much gas I have

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I would like to know what is wrong with it . It says full then it goes all the way down to empty . What is the part I need to replace and where is it located
My car has an automatic transmission.

The fuel sending unit is in the fuel tank mounted to the fuel pump assembly. The sending unit is shorted or open and needs to be tested using a gauge tester or by removing it and measuring the resistance of the sender by hand to see if it is working correctly. If you want to have this looked at, a technician from YourMechanic can come to your home or office to inspect the electrical wiring in your car to see if there is a simple fix, or if the car will need a sending unit replacement.

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