On the S5 manifold, there is a metal tube that protrudes from the lower intake manifold towards the firewall, from there a thick rubber hose goes to another hard line, and the hard line goes to the brake master.
If the pedal is soft, then that means the vaccum is fine, your brakes are just mushy... If the vaccum was bad, then the pedal would be harder to press, because the brake booster isnt working, AND you would have a hella vaccum leak too!
