91 escort is gettting too hot

over the last two years of owning my 1991 escort gt I have seen the "check coolent" light flash on once every month or so. The tempeture would always be ok. When this happened I would add water/coolent and then the light would go off.

Recently, the light doesn't come on, the coolent level is full, but the temp. of the car is getting to close to overheating. I cant drive it for more than 15 min before it gets too hot.

any thought on what needs to be done?

May be a bad temp sensor but I would change the thermostat just to be on the safe side.

You're barking up the wrong tree here. The "Check Coolant" light means the coolant reservoir is low. Has nothing to do with the cooling system itself.