For 1990-2009 cars

# DELAYED MOVEMENT FROM DEFROST TO HEAT POSITION

THE 1981 CUTLASS MODELS MAY EXPERIENCE A DELAYED MOVEMENT FROM DEFROST TO HEAT POSITION DUE TO LOW VACUUM. THIS SITUATION IS MORE PREVELANT WITH THE BLOWER ON HIGH SPEED. MOVING FAN SPEED TO LOW WILL ALLOW FASTER CHANGE OF VACUUM OPERATED DOORS. THE VOLUME OF AIR CIRCULATED BY THE HIGH BLOWER SPEED PRODUCES A GREATER FORCE THAN THE VACUUM PULLS ON THE MODE DOOR THUS MAKING THEIR OPERATION SLOW. THE MODE DOORS WILL EVENTUALLY OVERCOME THE BLOWER AIR PRESSURE HOWEVER THE MODE DOORS WILL OPERATE QUICKER WHEN LOWER BLOWER SPEEDS ARE USED. THIS CONDITION IS CONSIDERED NORMAL.

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