On Monday, December 17, 2007, at 02:13  PM, Automatic digest processor
wrote:
> Date:    Mon, 17 Dec 2007 15:29:54 -0500
> From:    AAG - Larry Word <word_aag@COMCAST.NET>
> Subject: 1985 Vanagon - New Year's resolution - AFM
>
> It's time to finally fix my "hunting idle" on my vanagon.....
>
> I drive this van daily but it's idle has been unstable - "hunts - with
> =
> peaks and lows" - for many years now...its idles like a old harley =
> motorcycle....
>
> Where do I start looking to fix this symptom?

There are two easy-enough possibilities; one is idle set too high, and
the other is a bad O2 sensor.

In the first condition the idle raise up until about 1500 or so, then
cuts abruptly down, repeats.  Screwing the idle screw on the throttle
body in (clockwise until the idle is around 900 rpm will fix it.

The second condition is caused by the computer hunting for the correct
mixture because it's not receiving a good signal from the O2 sensor.
If it goes away by unplugging the sensor, you need a new one.  They do
wear out and/or can be damaged by a rich running condition or if you
overfill the oil.

Hope this helps,
Gregory Smith
Olympia, WA
'84 Vanagon
'88 Vanagon
'87 Bertone X1/9 Corsa