Mitsubishi: Overheating, engine thermostat, mitsubishi galant

Question
Hi, I'm London and I have a 2001 Mitsubishi Galant, 4-cylinder.  It has been running hot since May 2006 and I took it to a mechanic and he supposively changed the thermostat.  It was working fine and then a month later it is running hot again but it only runs hot when I stop the car. As long as I am moving it does not run hot. I thought it was the fan.  The fan runs but when I am at stop lights I don't hear them run but when I was at a drive through window they were working.  Someone also told me that it could be the fan relay that needs to be replaced. There is no sign of leakage and the heat runs fine.  I have not had a Diagnostics performed. What could it be?

Answer
Hi London,

It isn't a relay, those never go bad. If it was, the fans would not ever come on. One is thermostatically controlled, the other comes on with the A/C. Both shut off at faster speeds. Possible bad fan thermostat. If it was the engine thermostat the car would be blowning steam like you read about. Pop the hood and see if they both come on with the A/C. Turn off the air and see if the one is still on. Let me know what you found.