If that fixes it, you’re all done and your wife will ride with you to the rock-climbing gym again. If a new temperature sending unit doesn’t fix it, then go ahead and replace the gauge.

For example, the water temperature sending unit can be tested for the proper ohm rating with the engine cold and then running at operating temp (thermostat open), or you can remove the sending ...

Troubleshooting the fuel gauge and sending unit is similar to diagnosing the temperature gauge. Disconnect the fuel-sending unit and ground the plug.

It’ll tell us the temperature of the coolant, independent of what your gauge is saying. If the engine actually is overheating, then you’ve got a serious problem.

Each sending unit varies resistance to current flow to negative ground. The coolant temperature sender in your engine's water jacket has an electrical conducting spring, temperature sensing ...