I've seen a couple post about this over the years.

I changed the vacuum manifold that's under the dash by the blower motor.
And I just tested that line that runs on top of the blower to inside the car today and still only blows from defrost vents and floor...

Anything else I can check?

This is very helpful
http://www.justanswer.com/pontiac/4g...nts-floor.html

But one. I have never been able to find the vacuum reservoir and two I'm pretty sure I don't have a Vacuum T on that plastic line that goes down the passenger side fender well by the battery. The same line that hooks to the top of the blower.

Thanks
Steven