Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Welcome, I'm Chris (aka Moose). Hopefully my assistance will be appreciated being the fees here are much less than dealerships.
I am sorry you have been waiting way to long on me or anyone else to try and help. I believe I can help on this concern if help is still needed.
Many settings use the AC even with heat in use. All air flow goes through the AC evaporator then through the heater core, then out the vents. All of your symptoms indicate the AC system is to blame and is turning your AC evaporator into an ice block that air can not flow through. You need to diagnose the AC system by first off checking the pressures to see if they are out of specs resulting in the evaporator getting to cold.
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