The AC blows hot air on the driver side and cool on the passenger

You may have an intermittent fault with the drivers side temperature door actuator. The actuator could be sticking at times causing the erratic temperature output from the drivers side vents. In order to try and confirm this you will need to check the a/c control module for fault codes. If there is a problem with any of the a/c actuators there should be fault codes stored in the control module. A scan tool is necessary to read the fault codes.