I have a 01 Silverado with a little overv 100000 miles on it. Very
occassionally, say every few months, I get hot air coming from the
vents and cannot get it to turn off. If I turn the A/C on, it still
blows hot. If I turn the truck off, usually for 15-30 minutes, it will
return to normal. The temperature gauge indicates normal temp range
when this is going on. Even with everything in OFF position I get HOT
air. Any ideas? Thanks!