AC not blowing through vests

Before I begin, I must say I have done extensive searching regarding this issue.

Here is the problem: AC suddenly began to blow through the defrost vents. I immediately suspected a vacuum issue. Switch will change to blow air at feet or defrost only. I began to start at the beginning of the system and work backward. This is what I checked:

• Vacuum pump works fine - builds vacuum and shuts off after 30 sec
• 4WD works fine - AC issue regardless of 2WD or 4WD
• Electronic Vacuum switch functions properly for HVAC and 4WD
• Gray vacuum line at heater hose plugged in securely
• Vacuum line to HVAC hold vacuum via hand tester beyond 20.
• Removed glove box and verified all lines plugged in and inspected for damage
• Verified blend door movement

After checking all of these components, the AC is no longer blowing out any vent. It appears that the system has trapped the air and you only hear loud air sounds. I can switch the selector to the floor and it will function correctly. No other selection appears to function.


I may try to disconnect the blend door actuator and physically move it to see if the position sensor is just off or the door is broken. Not sure how difficult replacing one of these would be.



Any suggestions would be great. Thanks!