I'm having HVAC issues with my 99. I was driving around town the other night, and I pulled into a place to eat. When I came back out, I pulled out and started driving down the road, and all of a sudden the floor vents started blowing hot air and fogged up my windshield in less than a second! I had my HVAC set to "Off, coldest temp". So I had to put the defrost on, and got the fog to go away. but then I noticed now that the floor vents always air out now when going down the road. I don't think they used to do that. But anyway, i want to know what may have happened to make it blow hot air out the floor vents when the setting was on "Cold", and fans were off. This was at night, about 70 Deg outside.