My girlfriend came to me the other day and said that her gas gauge stopped working.
There it is, full tank of gas and the needle sitting on 1/4 tank.
When the car is off it still sits on a 1/4 tank.

Where should I start looking

again, 1997 Outback Sport 5MT

First get out the owners manual and find the fuse for the gas guage and check it. Next remove the rug in the rear compartment and unscrew the cover and check to see it the electrical plug is corroded by unpluging and cleaning and reconnecting. If the float is hung up for some reason maybe a sharp rap on the top of the pump will free it. Can't think of anything else at this time. Ed