"90" climate control

[BLEVINSBK at aol.com]

      I was helping a coworker today on his 1990 "90" auto. with a
nonfunctioning climate control system. The car gives no heat to the cabin.
There were no fault codes stored in the system, After close inspection and
some removal of ducting, I discovered the foam covering on the air mixing
door has disintegrated. Now the forced air is apparently bypassing the heat
exchanger totally. It flows around and through the evaporator only. My
questions: Can you purchase the mixing door separately? Can you separate the
mixing chamber from the evaporator chamber in the car without removing the
complete matrix and freon? Any input is welcome!
    Thanks!


             Brian,  Md.
             '86 5kcstq
             '88 80q