What does this set up do?

[gumba]

The hose runs from the back of the i/c to the auxiliary air valve to the idle air control valve back to another outlet on the i/c. The small nipple on the back of the aux. air valve vents to atmosphere. Is this actually doing anything?

[jwasbury]

probably not. that is yet another throttle bypass device...only was on the earlier models as far as I know. my '79 had one as well...no vacuum line hooked up. if memory serves, this valve opens to allow air to bypass the throttle body when a vacuum is applied to the nipple. The vacuum line to the nipple would have had a thermo-time valve on it, which would block the vacuum to the AAV after a certain amount of time. you may notice an unused wiring harness plug floating around back there that would have gone to the thermo-time valve.

This was basically another cold-start fast idle gizmo. On my car it was one of 3 such gizmos from the factory:

1) Aux Air regulator
2) Aux Air valve
3) thermo-time valve blocked ignition timing vacuum retard for 60 seconds or so

[gumba]

More dead weight, soon to be less dead weight,thanks.

[T77911S]

those 2 should not be in series like that. i would remove the decel valve and plumb the AAR back into the maniflod.
i dont know what year your car is but mine is plumbed back in about where the DV is, kind of under the throttle body.

[RarlyL8]

As Jacob stated the AAV is found on early 3.3L engines such as the 930/63 California model.
I removed all the non essential CIS components from the Red Rocket engine except the thermol time switch for the distributor. I used that during the warm up phase and it worked well in my environment.

[T77911S]

i removed my AAR for a while. i ended up putting it back on. i liked the 2-3 minutes, at the most, that it helped the idle when cold.

if you look at the vacuum diagrams, the TTV that brian is talking about is in line with the vacuum advance, i moved it over to the vacuum retard to also boost the idle when cold.

[gumba]

Looking at it closer, the lower hose T's off into the manifold just before going into the AAV. At some point the AAV opens and dumps back into the i/c.
The engine won't idle on it's own for the first few minutes when it's cold. When the engine starts I depress the gas pedal slightly to keep it running. I do this for the first 4-5 minutes then it's fine.