Outside air vent not closing

[leddzepp]

I have a truck with A/C, and when I select outside air on the controller (moving it to the right), the vacuum actuator opens the vent on the passenger kick panel and lets fresh air in with no problem. However, when I move the slector back to the left, the vent door remains open and will not shut. I have to reach down and push it by hand. Does my vacuum actuator need replacing? Thanks. Yes, the engine is running when I am doing this

Also, the vacuum actuator on my cowl opens the vent door on the cowl when inside air is selected, and closes the vent when outside air is selected (the opposite of the kick panel vent). This is correct I assume? Thanks again.