The gas gauge would read empty even right after I filled the tank (I always shut the engine off...keys out of ignition...while filling the tank). Then the gas gauge would move in a random manner so you never knew how much gas was in the tank. My car also has the electronic display (mpg, dist to empty, etc) and it was wrong too. The dealer replaced the sending unit first. That did not fix the problem. The car then quit on me while I was driving about 35 mph. The dealer took the gas tank off and found that a baffle had come loose from inside the tank and had damaged the fuel pump. So in the end he replaced the tank, the fuel pump, and the sending unit. Ford covered this repair under an "after warranty" program since my car was out of the factory warranty.