I would personally suggest replacing the O2 sensor first.  If this doesn't
do the trick, try the AFM capacitor fix.  If you need directions, I'll
p-mail them to you.
Karl Batzler
84 Vanagon
87 Audi 5000 S
La Quinta, CA
-----Original Message-----
From: S Sittservl <Ssittservl@AOL.COM>
To: vanagon@GERRY.VANAGON.COM <vanagon@GERRY.VANAGON.COM>
Date: Tuesday, January 26, 1999 4:15 PM
Subject: Advice needed: engine speed jumping abruptly

>I'm looking for advice on a problem I'm having with my '88 Westfalia.
>I've seen messages from others with similar problems, but I'm not
>sure if quite the same thing.
>
>When I've run the van at highway speeds (70 MPH) for a few hours,
>the engine begins to drop around 300 RPM every once in a while,
>causing the van to slow abruptly.  After about 1 to 5 seconds,
>the engine returns to its normal speed (and the van jumps ahead).
>Occurances are anywhere from a couple of seconds to a few minutes
>apart.
>
>If I pull off and let then engine go down to idle speed, it will die.
>It has a little trouble restarting, but not too bad - I've always
>been able to restart it.  If I let the van "rest" a while - somewhere
>between an hour and overnight, I think - the problem goes away.
>(It will return after a few more hours of driving, though.)
>
>So far I've only experienced this in cold weather, but I don't know if
>that's affecting it, or if the problem just happened to get started
>in late fall.  Also, I don't know that "highway speed" is necessary -
>I haven't had the opportunity to drive the van for hours at a time
>at slower speeds.
>
>It's time to replace my oxygen sensor - could it affect this?
>
>Thanks for any advice.
>
>                                       -Steven Sittser