How do I check/ test heater control valve on 1991 Lincoln town car Cartier ? on 1991 Lincoln Town Car

Ac starts cold then warm then cold, blend door free and seems to work.

by in Glen Saint Mary, FL on September 17, 2012
1 answer
ANSWER by , September 18, 2012
It is a vacuum operated valve that you can manually open with a vacuum pump to test operation.