Turn the ignition switch to the on position and watch the gas gauge. If everything is functioning correctly there it should cycle through moving the needle through the entire sweep of the gauge. Now check your switch to make sure that the gauge is switched to the proper tank. If you have 2 tanks it should have a left and right on the A10 pannel. Finally, with the gauge turned on trace your wires going to the tank. There should be butt connectors on the wires, make sure that those connectors are connected well. you might even check if you have juice running through them with a multimeter, or a line tester. On 2 of my cats those butt connectors were the culprits of the gauge not working. Corrected that problem and none since. Some people have had problems with the sending unit in the tank. That is where the multimeter comes in handy because if you have juice going to that gauge and no results on the dash it probably is the sending unit.
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