This seems like two separate issues to me. The overheating and the heater not working. The heater not working could be most likely caused by a cranky heater control valve, the overheating might take some searching to get to the root cause. When does it overheat, in traffic on a warm day? Or does it seem to just be running warm all the time? Rasmataz is correct for having the thermostat be the culprit, but lets see if it can stand alone so we can get to the root cause before we just start throwing parts at it. I am running around a bit today and will try to check in in a couple of hours.
Tuesday, January 11th, 2011 AT 4:42 PM