The blend air door wouldn't cause this problem. The vacuum ball could. Have you checked to confirm you are getting good vacuum to the control panel on the dash? If you do have good vacuum, then the vacuum ball isn't the issue. Since you replaced all vacuum hoses, my first guess would be the switch on the dash which directs vacuum to different vent doors isn't working.
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Monday, July 14th, 2014 AT 8:50 PM