This has been a normal occurrence of every car I've driven going back to my 1991 Buick LeSabre. Read here to learn more:
www.quora.com
Why does my car AC vent blow hot air when driving even when the AC is off?
Michael Flatman's answer: Well everyone seems to be typing random answers which don't answer the question, so I will. Hot air comes from the vents when the AC is off due to ducting “gains” (heat we are talking about). Your HVAC ducts are likely a big snake across warm components, around a heat e...
