Alright, I went to work yesterday morning and my heater was blowing cold air. I thought I would freeze before I got there. I have a 2003 Chevy Malibu. I'm driving my old work truck until I can see what is wrong. Any ideas?
I second that motion---sounds like a bad thermostat. In my experience, there's no real warning signs. One day you go out, turn the heater on, and just a blast of cold.