I found that the recirc should only be closed (no outside air) only if the outside temp is greater than 90F or less than 20F to get heat and cooling fast. But, even then "I" leave it open and just close the outside air vent in the center dash, which makes a world of difference.

To get to the source of the clicking sound, the glove box needs to come out. I just did this to my 1998 a couple of days ago: Sprayed the lever where it attaches to the vent damper with silicone lubricant. Works much better now.

Your vent motor is working, otherwise you wouldn't hear clicking. The damper might be stuck or the plastic lever broken.

When removing the glove box, I took off the cover for the light to get enough grip on the box to pull it out.

Klaus
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Always willing to listen, just not able to take direction.