My A/C door is staying open. Can anyone tell me how it's supposed to function? To my understanding it's just on MAX A/C that it closes? Is the temp adjustment supposed to move it at all? I can push it closed and it will open when I turn the heater on. But won't close.

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Also I think my top vacuum line that goes into the firewall is broken. I'm assuming this is my issue since the actuator functions. I tried to remove the line with the glove box removed but it just pulls and doesn't pop out. How can I remove it so I can splice it or run a new line? Do I just need to pull harder / keep pulling?

 

I couldn't get your full size image to work but yes the vacuum line that powers the actuators runs from the port where your red line is to the brake booster. At least it does on my 1990.