Yes
Yes
No
Prolly have a vacuum line off, possibly in the engine compartment. A more likely cause is gonna be in the control switch(es) in the console. The vacuum switch there can/will dry out over time, and create what amounts to a vacuum leak, so when you move the lever to change the "mode", there is no vacuum to pull the servo and change the door positions.
If you can get in a really quiet area, start it up, close the doors/windows, and listen around the HVAC control in the console for a hissing noise as you move the lever slowly from position to position, stopping in each position for a few seconds to allow the switch to complete the vac. circuit. If you hear a constant hiss, that will be a vacuum leak. You may normally hear a little hiss as the doors change, but a constant hiss is a leak.
You'll prolly wind up changing the control..
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Joel Adams
C3VR Lifetime Member #56
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