AC not blowing out top vents

[dickeymoore]

I have a 1979 Malibu with original AC the AC will not blow out the top vents no matter what I do I changed all the lines but if I drop the glove compartment and put my hand up top of the box the AC is blowing out top of the box and not out the vents anyone knows what the problem is

 

[pagrunt]

If it's not a vacuum issue you might have blocked ducts & the foam seals are so bad that all the cold air bleeds out. Only way to really check it out would be pulling the dash.