Hello, I'm Cam. Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please be detailed.
When driving my Silverado 1500 LS with the AC on, the heat will suddenly come out of the driver's side while the cold air continues out the passenget side. Even while using the vents only, the heat will sometimes come rushing out of the driver's side and not the passengerside. If I turn off the ignition and then right back on, the problem goes away for 10 min, 20min, or whenever it feels like doing it again.
This is a very common issue. THe fault is with the temperature door actuator. On these vehicles, it is the easy one to change. It is under the center of the dash, towards the right side of the transmission hump. This is something that can be easily changed. HERE Are instructions. It costs about 200, and I would get it form GM. The part number is XXXXXIt should take you 30 mins.
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