Fuel guage is not working - 1991 Chevrolet Lumina

No issues with the fuel guage that I know of , but you can follow the basic troubleshooting guidelines. Starting with the wiring disconnect at the fuel tank for a bad connector or bad connection. Only other connection would be up to the instrument cluster in the vehicle. Only replaceable items would be the guage or the sending unit in the fuel tank. You can disconnect the return line circuit or connector at the at the gas tank and jump a wire to the ground the that feeds the gauge and see if the guage moves, but don't and i repeat don't hold to long because the guage will go over hard over and could damage the guage. If the guage moved and I would suspect a bad float on the sending unit or a bad sending unit, either case the fuel pump assy would have to come out for repairs.

yes

lamp burned out, ?
but does the fuel guage work 100%
and at what tank level do you expect the lamp to come on.?
did you read the FSM on this, its covered
or alldata.com?
free.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service

on this car, the PCM reads the fuel level then sets the fuel guage
and if the level (voltage from tank sender) is below a specific
voltage , it glows the lamp, low fuel
so if the fuel guage works, and the lamp is dead, the lamp is burned out. (or conn. bad to it)

In almost every case the fuel gauge issue is caused by a defective fuel level sending unit inside the fuel tank, it is an open circuit.

The gas guage does not have its own fuse but instead gets its power from the "integrated power module" that handles power delivery to the entire instrament cluster and beyond. If the guage is in-op,[doesnt work] then you will need to have a few "hands-on tests run to verify if the sending unit in the tank[fuel pump module] is functional or if this problem lyes else-where, wiring problem, bad ground,ect,ect.. One hint would be if the low fuel level l;ight still functions without the fuel guage working,then your problem is NOT in the tank and very likely is in your dash-electrical or faulty guage.
8w-40-2
8w-40-2

replace the fuel pump assembly, comes with fuel pump, new wire harness, and new float

SOUND LIKE FUEL GAUGE IS FAULTY.IF YOU REPLACED FUEL PUMP ASSEMBLY WITH NEW FUEL LEVEL SENDING UNIT.PROBLEM IS IN THE GAUGES.

Bad gage

FUEL SENDING UNIT MAY BE BAD/SHORTED

drop fuel tank. if guage moves all around its probably the fuel level sensor on fuel pump assembly in the fuel tank. If the guage stay's in one spot its the guage , replace instrument cluster assembly. you can take just the glass off the cluster and move the fuel guage needle and it will work (if stuck) but for how long? The wires to the guage come from the sending unit to the power train control module to the instrument cluster. pray its not in the wiring.