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Subject:Re: AFM adjustment; clockwise or anticlockwise?
From:Dennis Haynes
Date:Sat, 16 Jun 2012 13:58:11 -0400

You're not going to improve fuel economy if that is your goal. Are you
taking the idle mixture bypass screw or  did you remove the cover and plan
to adjust (tamper) with the main spring. After the engine warms up and goes
into closed loop, (O2 sensor control), the AFM meter adjustment becomes moot
unless you get it far enough out of range the O2 system can't compensate. An
excessively lean mixture increases NOx emissions and reduces power and drive
ability. Over time or leaned excessively you will eventually save a lot of
fuel while you replace the burned valves and pistons. Seriously, fuel
economy is not just about simple adjustments.

Back to you question, the idle air bypass turn counter clockwise to lean.
For the spring tighten to lean.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
HotelWestfalia
Sent: Saturday, June 16, 2012 12:26 PM
To: vanagon@GERRY.VANAGON.COM
Subject: AFM adjustment; clockwise or anticlockwise?

I don't remember if this was mentioned in this century.

How to adjust the AFM for more or for less consumption.  Which direction to
turn the adjuster to achive either.
I can't find instruction in the Bentley.  Maybe many of the members would
like to know this.

Zoltan