Stuck or slow moving Gas Gage

My neighbor has a '99 Sable that she told me yesterday the gas gage hasn't moved down in a week. She says usually it would be between 3/4 and 1/2 with the mileage she drives.

Looks like a special gage tester to check these systems according to the shop manual. Also does anyone think the gage could be at fault? or is it usually the sender in the tank? A real pain on these newer cars!

Any ideas will be appreciated. Thanks

Usually it is the sender. Using a multimeter you can send the guage some false readings from where the sending unit plugs in and see if the guage moves. You will need to check to see how many ohms a working sending unit puts out first.

Usually it is the sender. Using a multimeter you can send the guage some false readings from where the sending unit plugs in and see if the guage moves. You will need to check to see how many ohms a working sending unit puts out first.

Can you get to the sender connection without dropping the tank?

On the passenger side in front of the rear tire just above the fuel filter, right at the fuel tank is the wire connector for the fuel pump and float sending unit. You will have to find a wiring diagram to tell you which wires are for the sending unit. Most libraries have a Mitchell's manual that you can look at for that information. If you do end up dropping the tank, make sure you get as much fuel out as possible. Empty it only weighs a few pounds. A half tank of gas, plus the tank, can weigh over 75 pounds.