It sounds like there is an issue with the fuel sending unit. The sending unit (located inside the fuel tank), provides fuel to the engine as well as fuel level signal to the gauge.
To access the fuel sending unit you will have to remove carpeting from the trunk, there is an access cover that will let you get to the sending unit.
You might find these articles helpful:
I have attached diagrams for your reference.
Please let me know of any questions.
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Sunday, September 26th, 2021 AT 8:53 PM