Im driving down the interstate with the AC on. The AC starts blowing warmer and warmer. I think "Oh must finally be leaking some Freon." Then the temp gauge starts creeping up all the way to the red. I turn off the AC crank the heater but I cant stop, Im in the middle of a high traffic bridge on a major interstate. With the heat blaring the gauge came back down to normal temp. When I get closer to home, I turn the AC back on. It blows warm, then slightly cold, than gets hot again and the temp gauge goes back up. WTF. Is there some kind of AC fan relay that's going bad? I have no clue what is happening here and its never happened before. Any help welcome. Thanks