I finished installing a new fuel pump in my gas tank this evening. Started it up to check everything out. Fired right up. But my Gas gauge went to Full, then crept bck to half full, then back n fourth, then to full again. I know theres just Under a quarter tank . What could possibl cause the gas gauge to do this? If the fuel sending unit were bent during instal ,it would just read a wrong reading maybe,right? Theres only one wire (purple) going to the fuel sending unit .cant be crossed wires. wow this ones freakin my brain out. Wish the gauge would just say somewhere.