thermostat

NOTE: I actually don't own a Grand Prix - a friend of mine who doesn't use a computer has one and asked me to post a message for them to help them troubleshoot a problem they're having. So any replies might take longer than usual since I only see them a couple of times a week. -- I'm trying...

Hi all so I own a 1998 pontiac sunfire GT with the 2.4L engine. Basically my symptom is when at idle for awhile, it will start to over heat. When I start driving the airflow will cool the engine and be fine. Naturally I assumed my thermostat because in the winter time at idle it would never get...