only defrost blows air

:screwy: i have a 97 explorer when air is turned on it onlly blows out the defrost & rear vents. is this vaccum controlled?

99% sure it is.

99% sure it is.ive looked behind the radio and behind the controls for any vaccum lines but cant find any. where else should i look?:frown:

see if this helps. May help, may not.

http://usera.imagecave.com/way2old/expacvacuum.gif