vacuum route
 

:scratch:Can somebody please tell me where this middle nipple on my upper intake manifold vacuum line meet, end or get connected? Thanks.

Is this an S4?

yes S4 NA

Isn't there a Vacuum diagram on the hood ?

That middle line on the lower intake manifold is for the primary air bleed sockets. It goes to metered air on the dynamic chamber not manifold vacuum. I dont have the s4 vac diagram off hand to tell you which nipple around the tb is metered or vac.

On a series four car. that nipple for the fuel injector bleed air connects to the front of the throttle body/dynamic chamber. You have three nipples up front there. One is a large nipple and that is NOT the nipple that feeds it. It's one of the two smaller nipples.

Which of the smaller nipples? Well one of the smaller ones goes to the vacuum rack on the left side of the engine to feed vacuum to the solenoids. The other small nipple is the one for the fuel injector bleed air.

Which of the two nipples up front is NOT vacuum? I forget right now. One or the other.

That's as close as I can come to an answer right now because I ain't a gonna go out and look at my car to find out which. Lazy.