Fuel gauge problem

[dmc1300]

I have a 91 lumina euro with 3.1 engine. Took car back from daughter recently and noted to my dismay, after running out of fuel, that empty on fuel gauge is just above the 1/4 fuel mark. Any idea what could be causing this problem and possible fixes?

[Blue Bowtie]

Welcome Aboard!

The gauge on the older bodies used a 0-90 ohm sending unit. These systems require that the gauge has a connection to the sender in order to pull the gauge down from the "FULL" mark. Therefore, the gauge will register "FULL" if the connection to the sender is interrupted.

Later systems (with the 35-240 ohm sender) operate just the opposite, and will register "EMPTY" if there is no connection to the sender.

In the older system, and additional resistance in the circuit will cause the gauge to display a higher than actual tank level. I'd suspect that the connections at the tank or between the tank and gauge are corroded or loose, introducing that extra resistance. You can verify that the gauge is working by grounding the purple sender wire at the fuel tank to force the gauge to the "EMPTY" end of the scale. If grounding the wire does not force the gauge all the way to the "EMPTY" mark, there is likely resistance in the circuit.