Hi all -- Question about my '93 C2500 (350 TBI automatic). The coolant temperature gauge stays at full cold. However when I crank the engine it goes to the far right then returns when I release the key. Upper and lower radiator hoses are nice and warm. I believe my wife said the heater blows warm but I haven't checked. The other auxiliary gauges work normally.

I figure the gauge isn't dead since it sweeps when we start the truck. Does this sound like a bad sender? (As opposed to a stuck thermostat?)

Thanks --
Aaron

 

Sounds like a bad sensor, which should be an easy fix.

 

Something you might try, with the key on, and the wire off the sending unit, what reading do you get? Then hold that end of the wire to a good ground connection , what reading do you get now?

 

I will try that and post results -- thanks!