simplified post: Where does this A I R check valve go? 84 Cutlass 3.8l v6, Thanks!

 

This is not an "A.I.R. check valve". This is a vacuum check valve for the vacuum reservoir (the black ball) on the firewall. The end with the single port goes to the manifold vacuum source. The port opposite that goes to the vac ball. The right angle port feeds the HVAC system. The intent of this valve is to allow the engine to pull a vacuum on the reservoir, but during periods of low vacuum (like wide open throttle) the check valve closes off the manifold and allows the vac ball to feed the HVAC system. Without this, the A/C would switch from the dash vents to the defroster vent every time you went to W.O.T.

 

Thanks Joe, That's what I get, for taking an online parts store photo at face value! I FINALLY got all these vac hoses connected right. I set the timing and took it for a test. Seems to be running good. I suppose I should receive my vac line 101 diploma any day now! Still have more work to do before returning car to my Aunt but it's getting there.