Adjusting his gas gauge is not the problem here - adjusting the gauge itself is for minor calibrations. He has a malfunction of the circuit and electrically something is wrong. And the contradictions in the posts as to what works and when have made trying to help any further a problem. IF THE GAUGE RUNS UP TO FULL with the sending unit connected and then drops to empty when disconnected - problem is the sending unit. New means nothing - I have found defective ones right out of the box many times. Sad but true - junk gets sold all the time. The only way to test a sending unit is with an ohm meter. IF THE GAUGE RUNS UP TO FULL with the sending unit connected and then STAYS AT FULL when disconnected - problem is not the sending unit-not the gauge - not the VR - it is a short in the wiring and yes, the circuit board membrane is part of the wiring. Until there is some clarification of what works and when - I can help no further.
What if the gauge is at empty, but only goes half way when the car starts? Even when I fill the tank it only reads half full but it does drop down to empty very slowly as I drive and such. Would this be fixed by adjusting the gears as maveruss1 wrote? Hopefully this thread can be revived!
I would do the test of grounding the wire at the sending unit to see if the gauge goes to full. If it does then suspect a faulty sending unit. You can bench test a sending unit with an ohm meter.
A bent float arm that allows the float to hit the top of tank before the resistor is at full sweep could cause the never reading full issue... As already suggested ground the lead that connects to sending unit on tank, if it doesn't sweep to full you have gauge issues, if it does there are sending unit problems...
So my issue is: it just does not go past empty...( yes the sending unit is new, power in the wires to it) does not move...
I know 100 bucks for a sending unit is a good deal if yours is rusted out....mine is just icky, and inside the sock there was a huge clump of very fine sediment. Is it a bad idea to take the unit apart (looks like three tabs holding it together?) and cleaning it out? The brass float is adrift inside my tank and needs to be soldered back on its perch if it still airtight. Is the sender part supposed to be sealed, or does fuel leak into it naturally? I would rather spend the 100 bucks on exhaust pipes that I dont have.
You are probably right....but I will disassemble it just to see what is inside! sorta like a 100 buck cracker jack prize.
I cleaned the sending unit with a soft wire brush. Then took it apart and cleaned the inside with a soft toothbrush, and rinsed it with electromotive. the wire broke off the sender and the other end as well, so both ends were tinned and soldered back on. Ohm tested after re-assembly......88 empty and 22 full. Also tugged gently on the wires to make sure solder job wasnt a hoax. So, if I find the float when the tank is off, I will solder it back on with a microtorch. A little out of spec. but will give a reading? I will hook it up to the wiring and see what the gauge says.
