Volvo Repair: fuel guage, volvo 740, empty tank

Question
Robert, I know you heard this one before. I have a 91 Volvo 740 turbo. All gages work fine except the gas gage. Thing is when I turn off the ignition the needle drops well below the normal stop point on the gage. When I turn it back on it pops up to a little over empty. Tank is full. Is it the gage itself or something else. Thanks alot, Ed

Answer
Could be both the gauge and the sender. Volvo makes a resistor you plug in place of the sender and the gauge will deflect to a certain position.You can pull out the sender and manually change the position of the float to see if the gauge will move.If you replace the sender make sure you get one with a new fuel pump on it