Temp Guage issues

Had same problem with my 74 Duster cluster gauges. Found the nuts that hold the gauge in and make electric contact with the pc board to be loose and the copper trace to be corroded. I would pull the nuts off the back of the gauge and clean the copper with some scotch brite to make hem shinny and then retorque the nuts and see what happens. The limiter maye be fine and with the high resistance connections can not do its job properly.