AAV too small at cold start?

Would you consider this opening at cold (60F) to be too small?

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Ehhh -- can you show the other side of the AAV body? Is this the adjustable type of AAV with the small nut and stud like this:

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I did readjust my ex-AAVs a time or two over the decades.

 

how is it adjusted

 

Are you saying that it does have the adjustment nut feature? If so, I just used a drill bit shank to put the shutter where I wanted it (maybe .156" or .188" -- I can't recall and no longer have my records), and loosened and retightened the nut. What is the symptom that you are trying to resolve? Just think the cold start RPM is too lowish?

 

Yup, cold start too low.

 

Are you sure that the AAV is closing when warm? A "dead" AAV would also give that symptom -- i.e., the AAV opening just stays constant, and, since it is all tweaked up for warm-running, warm-running is fine (even though the AAV is wrongly a little open), but no extra air is allowed in during cold start-up. Just something else to check...

 

Yes, I removed it from the car, attach it to 12V battery, and it closes totally in about 10 minutes.
Which is also a reason to not make the cold orifice totally too big, or it would take a long time to close up.

 

Well, I tried adjusting it and it did not get a whole lot bigger. The adjustment rod is maxed out against one side of the eccentric hole and that is the max it's gonna be. I guess I might need a new one afterall.

 

Just wondering since the orifice is so small, why is the hose connected to the AAV is so damn big why couldn’t be the hose the same size as the orifice?

 

Mitchell's picture is at 60 deg F -- at 32 deg F (or lower) it will be more open. Also, you want all of the flow restriction to be in the "shutter" portion, not in the hoses nor the hose mounting nipple IDs (so different models using CIS with different AAV hose lengths get the same behavior with the same AAV) = pushes the Engineer to use a seemingly oversized hose.