The Vanagon engine is known for this. The usual cause is what is known as a "Lean Mis-Fire". The cylinder fuel and air deliviery is slightly off balance and due to the lean mixtures, one will be lean enough to mis fire. This is the most common cause of high HC readings during emissions testing. This is lso an unusual operation so it may not be an issue to be concerned with. Do you feel any miss or power loss under load? Does it pass emiossions testing? A bad valve, piston or cylinder problem, or a vacuum leak will also cuase this condition.

Dennis

----- Original Message -----
From: Jeffrey Olson <jjolson@GWTC.NET>
Date: Friday, February 24, 2006 5:00 pm
Subject: Miss at 3000+ rpm

> The other day I stood behind my new used 85 GL and held the throttle
> open and heard an intermittant miss in the midst of a very smooth
> 3000+rpm.  Any ideas?
>
> Jeff
> Martin, SD
>