Fuel gauge is giving me faulty readings. Did insturment cluster selt diagnostic and gauge went from full to 3/4 to 1/2 to 1/4 then to empty. Unplug sending unit gauge goes to empty. Jump sending unit wires at sending unit, gauge goes to full. Tested 3 different sending units out of tank every time they are pluged in gauge goes to 3/4 when empty move it to full, gauge goes to full but never empty. checked resistance on sending unit empty 1075 ohms, full 70 ohms. With smooth increse between. Orignal sending unit was definately bad, it had very speractic readings. Now what