I have never understood why Dodge used the systems that it does to control the Heat / AC diverter door. The vacume devise is at best overly complex. I'm wondering why an old fashoned push/pull cable would not be better. Why not re-engineer it? "Choke cables" are cheap.

You could the old Dodge Van and truck were pull cable type vent once long ago. But even back in the 70's that I remember all the vehicles with A/C had vacuum even then. It was just the heat only system that had pull cables. Now on the 94-98 bodies the blend door is cable twist cable operated but the rest is vacuum controlled.

I'm pretty sure my 97 Cirrus is twist cable. Heat / AC