Vacuum line leak?

Just purchased a 97 blazer w/110,000 miles on her. Noticed that air blows through defroster vent even though selector is set to front vent, even more noticable when going up hill, Any ideas? Thanks in advance.

Open your hood attached to your hood is a plastic ball it should have a vaccum line attached to it. This is your vaccum tank, if the line is off then the A/C defaults to the defrosters.

Thanks, that was the problem. Found the vacuum line tucked away.:bananasmi :bananasmi