I Have the same problem this person has, but today my car went into the red (260). I stopped to see what was wrong , no water was boiling over , no signs of the carrunning hot. after a while i heard a clicking noise and the gauge returned middle ways. It only looks as if it is running hot when i am stopped in one place for a while. As long as i am driving i can run the air or not and it stay 1/2 way. Could this be a sign of the water pump going out, or theromastat. Where can i take it to find out what's wrong.