89 LXi temp gage pegged

My temperature gage is pegged all the way to "hot". This happens immediately after the key is turned to the ON position - even after the car has been sitting overnight. When I turn the key to the OFF position, it the gage drops back down to "cold" like it should. The cooling fans appear to be working properly and coming on when they should be and staying off when they should be. This makes me think something is wrong with the gage itself. I'm thinking if a sensor was bad, the car would act like it is overheating and the cooling fans would turn on even when the engine is cold. Any thoughts?

you got short somewhere in temperature gauge circuit. look at thermostat housing and find temperature sensor. its 1/4" diameter thing screwed into thermostat housing, there should be one wire come off of it. if that wire is shorted to ground gauge will go up to red mark.

I will check this out...hopefully sometime over the next few days. I do recall seeing this particular sensor.

Replaced the temp gage sender switch for $13. Works fine now. Thank you!