Do we only have on of these in the car on the passenger side?

I have looked at the vent while the car is running but when does it open up?

Could I just unhook the thing vacuum line to keep outside air and dust form coming into the car?

Thanks

 

That is the recirculation door. It opens when you put the HVAC control to MAX A/C.

 

Thanks...For anyone know where the cowl vent feeds the blower motor? Is it that hole that is directly on front of it? I've only seen pictures but IM sure someone know where the cowl vents feed the blower motor.

 

Through the firewall.

 

Where in the firewall? Passenger side?

 

Yes, that's where the blower motor is.