There are two concerns with this practice. How many cycles can the starter
take and depending on conditions the effect stopping the cooling system can
have on the engine. Especially after an extended highway run a 1-2 minute
idle down will prevent heat soak from creating a temperature spike and
stress head gaskets and stuff. Vehicles designed for this type operation use
electric water pumps to maintain some coolant flow. Audi turbos also used
water pumps and fan controls for after cooling. Some even had
injector/manifold cooling fans. To deal with this.

The concept sounds good as anytime the engine is running when the vehicle is
not moving you are getting 0 miles to a gallon.

I really don't know the magic number. In New York trucks are not allowed to
idle beyond three minutes except for warm up and when the outside temp is
below 25F. When I bought my motorhome in 2004 it was pre-programmed to shut
off after idling for three minutes.  Was that a coincidence?

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
pickle vanagon
Sent: Saturday, June 16, 2012 7:25 PM
To: vanagon@GERRY.VANAGON.COM
Subject: when is stopping/restarting better than idling?

I guess I'm looking just for the range of educated opinions of the
listmembers.

In a well-maintained Vanagon, how long does a stop have to be for it to be
better to stop the engine and later restart it, versus idling?

10 seconds, 1 minute, 5 minutes, etc?

I'm wondering about the theory of it, not the practical aspects as relate to
the needs of actually driving around other vehicles...

-Wes