Then I would try bleeding the air from the system and go from there. If you aren't familiar with the procedure, there is a small bleed screw on top of the thermostat housing. With the car running and hot, open the bleeder screw and watch for the coolant to stop spitting out and have a steady stream. Close the valve and drive it a bit. Make sure your overflow is full and then let it cool down. Check the rad level once cool and see where you are at. Top off as necessary. These cars can be hard to bleed sometimes. I had to do my 00 GT twice to get all the air out.
