Date:         Tue, 7 Dec 2010 22:31:36 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: I was wrong -- how the AFM *really* responds...
Comments: To: Larry Alofs <lalofs@gmail.com>
In-Reply-To:  <AANLkTi=6PiMHJLeRXABjg5DbzSi93Jh9pWxQoxSMpxLj@mail.gmail.c om>
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At 08:20 PM 12/7/2010, Larry Alofs wrote:
>Seems to me you were right about the way the vane in the AFM
>overshoots.

True; but I already knew that from watching the vane on the old
beast.  But my idea that the acceleration of the vane on abrupt
opening would be greater than on closing is shot completely in the head.

>   The question remains about whether the ECU actually makes
>use of that part of the signal in a constructive way.
The injectors fire once per revolution, supplying half the charge for
a given cylinder each time they fire.  So at 1500 rpm they'll be
firing every 40 milliseconds.  If the ECU only looks at the AFM that
often it's not likely to see the peak value which seems to be only
about ten milliseconds long.  But I expect it looks more often.  If
it looks every five milliseconds it should catch the peak.

>   Someone should disassemble the code in the ECU program.  :-)

Prolly should get in touch with these guys...
http://www.thesamba.com/vw/forum/viewtopic.php?t=382053&start=80

Yours,
David