Bob, your theory is all wet (frosted?). It isn't the spark + moist
air that causes a frosted plug. Rather, it is simply the water vapor
in the cylinder condensing on the subfreezing plug -- the spark plays
no direct role in the process.

Not true of my experiences.

Ice MASSIVESLY collects BETWEEN the electrodes...
*NOT* EVENLY distributed over the general surfaces of
the 8 or 16 spark plugs.

Have you ever observed what I'm referring to?

Bear in mind, this phenomena does not occur until
SPARK is introduced to the environment.

The water vapor in the cylinder can
come from air being pumped through the cylinder before the engine
fires (see 1) or, more commonly, from the combination of ambient water
vapor and water vapor liberated through combustion in a failed start
(see 2). Although the spark does play a role in the latter case, it
is a decidedly indirect one.

David O --

Are you saying the failed start causes the ice,
not the other way around?

Hmmmm.
If so, most interesting......
Even though my experience has demonstrated otherwise,
time and time again.


Barnyard BOb--