Hotcobra, thanks for the information! Looks like pretty basic troubleshooting, so I assume the information you supplied for a 2003 would also apply to my son's 2001? Interesting addendum to the saga of my son's car. He and a friend removed the thermostat. The car has not exceeded 180 degree temp the last few days! The last time we pulled it out, we checked that it would open in a pot of boiling water. It is not a Motocraft part, but is one we bought from AutoZone. I also checked, double checked, and triple checked that we put it in the correct way. Weird. For now he's running without a thermostat and is pretty happy.