I've got a 1996 Formula and it seems to overheat on me. When im traveling down the road the temp. is fine, i'd say about 185 and when it sits and idles it runs over 210 and keeps going up and it will drop back a little and then go back up and back and forth it goes. I've replaced the thermostat. Fan's work fine, doesn't have a head gasket leak. And i have an infered laser and it say's that heads are at 185-190 and i check the radiator not to hot. I'm running out of idea's, could it be a bad gauge...Any other idea's would be greatly appreciated. Thanks

 

Got the same problem. I did my temp sensor on the block 3 hours ago. So far so good. Also do the sensor in front of the water pump. Bleed the coolant, while your there change it.

 

Doesn't sound like you have a problem. When you stop, so does air flow across the radiator. The engine heats ups and the fans come on when the ON temp threshold is met. The engine cools and fans go off. The cycle repeats if you stay still.

 

Keep in mind too that these cars do run warm from the factory, it does sound like normal operation.

 

Sounds normal, at idle your car will fluctuate back and forth from about ~200 - 226.