I have a 1983 mustang GLX that came as a original six cylinder auto. I swapped in a 87 302 and a t5 manual the converted to EFI and all of a sudden my fuel gauge isn't working. I tried ordering a sending unit for 87-93 but then instead of it just reading wrong it had no response at all. The Gauge and wiring is all good. So what year sending unit do I need an 86?
The ohm range on the 87-93 is different so it will read incorrectly, but it should still cause the gauge to move. If you have validated the gauge and wiring are good, the sending unit you would need for the 87+ tank and your 83 gauge would be this one. It is physically identical, but the ohm register is specific for 83-86 cars.