For the past 3 winter seasons, my heater blows cold air when stopped at a traffic light/stop light. It's a 2001 Eclipse GT. I took it to the dealership 3 time while it was still under warrenty and they said that there was nothing they could do. They said it was the way it was made! Oh well, how ridiculous is that. The problem did not exist the first year or two. The defrost ONLY BLOWS cold air while parked and idling. I can leave it running for 30 minutes with frost on the windshield and it will not even get warm. As soon as I start driving.....boom.....it heats up. Any one have any knowledge of what could be wrong?