Hi David,
not talking about idle here.
it's about 'during deceleration' .

I wouldn't say 'AFM closed' myself.  I might say 'at rest position' .
Of course there will always be some air flow through it since in both
versions of wbxr throttle body throttle plate there is provison for air
flow r with throttle plate fully closed, one has a hole in the throttle
plate, the other is flat on one side ..some air always flows..
so if it's flowing there ...at closed throttle decel, or at idle,   air
has to flow through the AFM.
The AFM  is never 'closed.'
'Closed' implies fully closed off.  There is no fully closed off mode I
sure don't think.
if the engine running in any mode, some air is going through the AFM and
throttle body.

yes, they sure wear on the sweeper contacts where they spend a lot of
time at that air flow/rpm.
I have seen an AFM that was uneven/weak right at 3,100 to 3,200 rpm ..
turns out on that particular syncro van ...in normal driving you were
right around that rpm a lot.
A brand new one sure smoothed out that van !

it's helpful to preef rood before sending. Mostly I do.
  - like  to see if what I wrote makes sense before sending .   I get a
little crazy when people make up new terms like 'idle plug.'

I certainly think 'at rest position' is a lot more useful description
than 'closed' for an AFM at idle or decel, or even engine shut off. It
probably just drifts or flutters off rest position at idle.   Never
closed fully so no air can flow at all.  There's no seal or anything on
the flapper door. . I don't know for a fact that there is some flow
thrugh an AFM at rest position ...seems like there would be though.
It's all good though !
sdf

On 6/21/2012 8:45 PM, David Beierl wrote:
> At 11:14 PM 6/21/2012, Scott Daniel - Turbovans wrote:
>> if you mean 'decelerating' and you are talking about the throttle plate
>> being closed, I would not expect the AFM flapper to move off it's rest
>> position in that mode.
>
> If you think about it, Scott, with the AFM closed there could be no
> airflow through the engine except through the idle bypass, and the ECU
> would not supply fuel since it would see no air passing through.  So
> it could never idle.  At normal idle the flap oscillates around a
> region of something like maybe a quarter inch open (if you have an AFM
> open, look at the wear spot on the carbon plate) and it would be
> farther open when decelerating toward idle even with throttle closed.
>
> Yrs,
> d
>