How do you fix a fuel gauge on a 1997 jimmy do i have to drop the tank?

Answer 1

Yes, the fuel sending unit is in the tank. You can test the unit without dropping the tank if you are handy with resistors, but it is a little difficult to get to. There are two plugs on top of the tank. It is the square one with four wires. You will need a 240ohm resistor (empty) and a 33ohm resistor (full) you will need to find out which wires go to the sending unit and short each resistor across them (one resistor at a time) with ignition on, have someone look at the gauge. Be carefull not to short the wrong wires...I have heard that it can cause serius damage to other parts. If the gauge moves, have fun dropping the tank, because you will have to replace the sending unit. I would suggest going ahead and replace the pump while you are in there if there is mileage on the truck. AC Delco P/N MU85 for a 4door model and MU1063 for the 2door model. Do not go cheap on the pump!!! Approx 66psi of fuel for truck to run properly. Cheaper pumps do not produce this over a long period of time.

Good Luck