You will need a new sending unit, and that is the small round puck on the left side which keys into the trim tilt pin. There are two 5/16″ headed screws (bolts) holding it. Two wires coming out of it also with one being a ground. If it is not still under warranty, which applies to the engine and parts, then you can sometime shim the inside coil keyway and put small amounts of pressure on it, extending the life. If its warranty, just replace it.