You asked: "During the summer, hot air rushes in by my feet. In the winter, it is cold air. What is not functioning properly?" The problem is due to a detached seal at the front of the AC/Heater air plenum box. Refer to 7-1-1 Parts Manual fig. # 19 You also asked: "when I turn on the AC, I hear a fan squealing for about the first 15 seconds it is on..." The squealing sound is due to a corroded bearing in the AC/Heater blower motor. DMC Joe www.dmc.tv "We're here to help you" DMC Help / De Lorean Services / <dmchelp@xxxx> [moderator snip]