Hello, all. My 1990 Mercury Sable has developed a problem(s) with dash/floor air and heat routing. Currently selecting the "vent" position only results in warm (rather cold like it used to) air being sent out the dash air ducts. Selecting "floor/panel" provides warm air out the dash air ducts but air flow on the floor is barely noticebable even with the "floor" only selection. The inside temperature selector appears to have no effect - air is always warm (after engine warms up).
My hunch is that a vacuum-operated servo(s) that controls an air diverter door(s) is non-functional but I would welcome any comment. Thanks for your time. Sincerely,
John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory
4555 Overlook Avenue, SW Washington, DC 20375-5337