any ideas??? my car will only overheat after driving about 20 miles on freeway and come to a stop. once moving the car will come back down to mid temp. i had to turn on the heat today in an accident so it would not overheat. i took to the dealer and they said they could not verify. i checked the coolant and made sure there was not an air pocket. coolant looks good, both fans are coming on. the car has 65k on it. when i come to a stop and it is on mid if i give it gas and rev only 500-1000 rpm's the gauge will rise. has me stumped. any thoughts????