Had a friend of mine following me in my Wagon tonight on the highway. We stopped at our destination,and he asked if my car was running hot? My Temp gauge didnt indicate it,so I wasnt alarmed.

What does a car thats running "hot" smell like?

I have noticed at times though that my temp gauge will go to the middle for a while,climb,then go back to the center all while driving at highway speeds.(Whats up with that?)