Ed, I've got the Audiovox CCS-100 on my 85 manual Vanagon.� I use an 
accumulator purchased from Napa (just good practice to have an abundant 
vacuum supply).� But sometimes the cruise control 
would disengage--I noticed it would happen after going after some bump in the 
road.� I think the root cause was that the bracket holding the sensor 
would flex and oscillate, momentarily increasing the distance between 
magnets and sensor, and the CC would lose itself.

Simple solution:� STRONG magnets and a STRONG bracket.� I replaced the wimpy magnets in the kit with some rare-earth� (neodymium) magnets
 available at http://www.gaussboys.com/ or similar, google to find a 
source maybe a hobby shop.� And a really stiff and strong bracket of 
heavy gauge steel I had laying around (Home Depot or Ace Hardware) to support the sensor in close proximity to the rotating magnets.

Excellent
 results!!!� My cruise control NEVER drops out anymore.� And I think 
having the vacuum accumulator makes for INSTANT response when I push the
 button---very solid.� A real pleasure to drive.� I'm really sold on that Audiovox unit.

Rich
San Diego

--- On Sat, 11/3/12, Edward Maglott <emaglott3@GMAIL.COM> wrote:

From: Edward Maglott <emaglott3@GMAIL.COM>
Subject: troubleshooting Audiovox Cruise Control
To: vanagon@GERRY.VANAGON.COM
Date: Saturday, November 3, 2012, 7:33 PM

hello, I have one of the usual aftermarket Audiovox cruise controls
on my 86 with AT.� I think it's model CCS-100?� I use the magnet
speed sensor kit on my drive shaft.� It's not working well.� It
engages briefly and then immediately disengages.� It will then
attempt to resume to that speed if I press that button, but
immediately disengage.� That makes me think that it is at least
remembering the speed I set it to.� I've gone through the
troubleshooting of all the wires as the instruction manual specifies,
and everything is good.� I'm wondering if I could devise some way to
monitor it from the driver's seat to figure out what is going
on.� Thanks for any advice.

Edward