ok..so i just did an A/C delete on my 88 Roc. when i change the controls from off to on it works just fine...all low-high works on the blower. but it will not change off of defrost(the lever moves just fine) is this vacuum controlled? i know there are two vacuum lines that enter just behind the motor and i know one has to do with the A/C (coolent routing solenoid, did the delete on that) so is it possible that the other line is for changing from vent to heat(feet), face and any combo there....

 

Yes.

Defrost is the default duct setting in the event there is no vacuum. .

 

thank you that is what i needed to know....