i have a 99 deville. it is running hot under a load(mountains,traffic,etc.) With the a/c on both fans come on but @ idle with a/c off neither fan comes on. it got up to 210 @idle and fans never came on. could a stuck thermostat cause this or could it have a bad sensor for the fan? please help!!

 

not enough details ...

idle temp and fan function sounds normal to me.

what makes you think its overheating?
what is the temp when you think it overheats under load?


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Its my bosses car. He said it was getting up to 226 degrees in the mountains of N. Carolina and in traffic but on the open road it was down near 195. I changed the thermostat and it now seems to be ok. It never got over 19o while driving and the fans kicked on @ 220 like I was told they should. I think it was a stuck thermostat but I will know in a day or two when he heads back to the mountains(we live near Daytona Beach).