Front AC not as cold as Rear AC on 98 Chevy Tahoe


I have a 1998 Chevy Tahoe with front and Rear AC. The front AC only get moderately cool; however the rear AC is ice cold. How do I fix this.

In the dash is a door operated by an actuator switch. The door isn’t shuting all the way allowing
outside air in the front. The rear has its’ own evaporator and fan system which explains why the two aren’t the same degrees of coldness.