On Aug 2, 2006, at 9:32 AM, Mike Kozak wrote:

> sealed the vent tube from the battery (I only have one battery and
> its on
> the passenger side) but that did not slow them at all.  Probably a
> dangerous
> vent to seal also.

I had the same issue -- my solution was to cut the top off a 750ml
water bottle (pop-top style) about an inch below the spout.   Leave
the pop top on, but open.  This can be wedged in the vent hole, and
will still allow air & fumes in & out, but will keep out anything
wider than a pencil.

Other entry points seem to be doors & windows, even if left open for
just a few seconds.   Once they get in the right side battery area,
there is a tube that takes them to the left side, which connects to
the cabinets, and pretty soon you have mouse poop everywhere.

The mice are smart -- i suspect that a group that lives near a
campsite may know entry points for  particular makes & models of
vehicles.   So another option is to remove all VW logos and walk
around loudly talking about your nice Ford van.   The mice won't know
where to look :-)