Defrost Problem

[Ryan's87]

My 87 GN's fan blower only blows out of defroster. All of vacuum lines are right and secure. Has anyone else had this problem or maybe know where I can troubleshoot it further?

 

[just plain john]

If all the lines are indeed secure and not leaking I would think it has to be the control head, or possibly the diaphram that controls the defrost door. Do you have a vacuum pump?

 

[charlief1]

Loss of vacuum is usually the issue here. Check the vac lines under the dash to see if you got any. If you do then I'd say it's the control head.