Date:         Tue, 30 Apr 2002 20:26:29 -0500
Reply-To:     John Clavin <jc@AUSTIN.RR.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         John Clavin <jc@AUSTIN.RR.COM>
Subject:      Tach Jumping
Content-Type: text/plain; charset="us-ascii"; format=flowed

The hesitation problem is still occurring intermittently on my 85 digijet.
So far, I can see nothing wrong with the digitool readings during any of
these episodes. However, today, I started seeing the tach jumping around a
little at idle a few miles after some hesitations occurred. I could not
detect any motion of the tach needle downwards from the idle point (~850),
but random, sharp "kicks" up to 2000-2500 for no apparent reason. Engine
idle sounded normal when this occurred.

I would guess this to be a problem with the Hall sender, but that was
replaced new last month. I tried jiggling the connector on the side of the
distributor but could not recreate the problem.

The idle stabilizer is also new (three months ago). I've bypassed the idle
stabilizer for now and am waiting to see if the problems persist.

Any ideas? Anybody have experience with coil or Hall Control Unit failures?
Spikes in the alternator output?

Regards,
John Clavin
1985 GL -- Austin TX