Hi everyone. I need suggestions as I inherited my mothers CTS last September and I am ready to sell. 2004 with 87000 miles. Car runs excellent, except for one minor flaw. When it get about 85 + degrees over here, the AC does not work.Just blows hot air. Otherwise, when it does work, it blows icy cold. Also, sometimes if it doesn't work, I turn it off, wait for about 5-10 min, turn on and then it blows ice cold, again, it cannot be above 85 degrees out. I work at a performance shop and they cannot figure out what is wrong. I want them to check it out one more time before I sell. Any suggestions for what they should look for? Yes it has been charged but like I said, it does blow ice cold...when it wants to.