General Maintenance & Repairs - A/c not blowing out the vent

I recently got a ms4 cammed auto car with a 3600 stall, the a/c works but only comes through the floor and dash not out the vents. The brakes are kinda iffy so i'm guessing it's a vacuum problem but idk, what do you guys think ???

You're on the right track, most likely a vacuum leak. Sounds like you're in "default mode." Check all the vacuum lines behind the intake.

I bet its the A/C heater vaccum check valve; right by the PCM, a tiny little buble plastic piece where 3 tiny rubber lines meet. I replaced mine 3 days ago cause I had the same problem :)

Got it for 2$ in a junkyard cause overhere, this part is not produced anymore and parts store dont have it! got it from scrap V6 model..