Overheating … in this case just means that the temperature gauge goes up. No coolant is lost. No radiator boiling over. Just watching the dashboard gauge. Subaru checked for air in the cooling system (it’s been in four times (Subaru - 2 times; other mechanic - 2 times) over the last 6 weeks for this problem). Subaru dealer did find air the first time; I will not take it back to the original mechanic. Subaru dealer has checked the temperature and it’s within “normal conditions”. Head gaskets have been checked and are fine. Other possibly relevant info: The second time I took it to Subaru dealer, they said the engine fan didn’t come on at first … but then did. I think it has something to do with that – otherwise, why would the heater and blower take care of the temperature gauge?