At 08:52 PM 10/26/2009, neil n wrote:
>Bentley shows air cooled, Digijet, and Digifant, charcoal canister
>bottom hose connecting to the air cleaner.
>
>Anyone know if the charcoal canister bottom hose on my VanaJetta
>should be connected to the air cleaner?

Yes -- any air input to the engine should be filtered

>Since the air cleaner is sucking on this hose, is that crucial to the
>charcoal canister operation?

Other way around -- the vacuum connection direct to the intake
manifold (through a 1.4 mm orifice) pulls filtered air from the
filter box through the charcoal and into the engine.  The other
connection through a much smaller orifice to the throttle body only
opens the vacuum valve to allow this when the throttle plate opens
far enough to pass the drilled hole in the throttle body.

Yrs,
d