The first place I'd suspect is the feedthrough at the sender on top of the fuel tank. Rust lifts the protective insulator from the sender's mounting plate and allows moisture to corrode the wiring until it is gone.

To verify, use a test light (with an incandescent bulb) to probe the gray wire at the sender harness. Shown below is a 245, but your sedan is even easier to reach this connector. It is under a plastic cover held in place with snap-in fasteners.

If you get light here, the gauge will respond a little, and you've verified your need to go in the tank to solve the problem. If unsure, ground this gray wire and you'll see the gauge peg at full.



In The Tank
--
Art Benstein near Baltimore

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