I cant seem to get any air out of any of the vents. Just the floor and defrost. Its in a 95 blazer LT.

 

Your vacuum supply to the HVAC system is either disconnected or plugged.

 

alright need better info that that...how can I test to see if that is the case?

 

Search is your friend. This very topic has been covered in some very detailed posts.

Here is one post I made a while back showing the schematic of a 97 Blazer which should be almost the same as yours:

 

The amount of searches I have done today is crazy. I have seen that schematic many times over...but it doesnt help me if I dont know what I am looking for. That schematic doesnt show me for what and where I am looking for something.

I have talked to some people and like you said one of the lines is either disconnected or plugged, which I have been told the lines start from right behind the ac/temp. controls on the dash...meaning I need to pull the dash to get to them? Or do I need to look elsewhere?

 

pop your hood, there should be a black plastic ball mounted on the inside of the hood on the driver's side near the hinge.....double check that there is a vacuum line plugged into it. if not, look directly down and it'll be staring you in the face. I had this same issue last week, sometimes it'll pop loose when you open the hood.

 

Excellent then I was in the right area. The line was brittle and as I was trying to pull it off the T and ball is broke at one side. So I need to replace the hose...but before hand the line was still attached and fine. So I dont think that hose was the problem. But is now.

 

Alright just spent some more time try to fix it. Pulled off the av control from the dash and made sure everything was plugged in, and working and all was. Checked under the hood from the ball down to the T, then from the vacumm line going from back of the intake manifold and the line as far down towards the firewall as I could follow it. Still no air flow from any of the vents. Plenty of cold air from the defrost and floor vents, just cant seem to get any of the cabin vents.

 

if the ***** is messed up you need to replace it...thats your problem...that line has to be plugged in or it won't switch the vents.

 

how would you be able to tell if that ball is messed up? also how would that ball control the passage of air from the defrost/floor/vents?