I turn my air to 90 degrees and the air on the drivers side is cold or cool not hot like it is supposed to be. The passenger side is hot. What could be causing this? Is it an easy fix.

Mine does the same thing!! really sucks when its -9 below outside. I havent found out what is wrong with mine either. Thinking of starting with the inside ambient temp sensor. I have heard of the control units go goofy.

Hey guys, I have a 96 bonneville with the same problem...... I have been sent here to check these pages out.....
Give them a try..... It could be the air mix acuator...... Good luck ....
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https://www.gmforum.com/t274213/

Is there an easy way to get behind the glovebox and move the actuator so it will be hot instead of cold.. How hard is it to remove the glovebox and get under the dash to move the actuator. I hear 2 terms of things that could be wrong, 1 the air mix actuator and the door mix actuator are they 2 seperate items, and how can I troubleshoot to see why I do not get heat in my car.