The Aux Air valve closes via a bi-metalic strip that is heated as soon as the engine is turned ON (not dependent on anything else). There are a few different part numbers for this valve and as far as I can make out the only difference will be the rate of closing as they seem to have different resistance's. However, if yours was working ok previously I suspect something has failed internally - it would be best to just replace it.
All the best,
Tom
84 1.9L Westy

John Baker wrote:

> So does the Temp II sensor "tell" the aux air valve when to close??  Is this likey the problem?  Is adjusting the screw on top of the AFM to allow in more air during cold weather a "cheat" way to offset this til O can get it fixed??
>
> Peace, JB
> '66 Split Window Camper
> '83 H20 Vanagon