One more thing I wanted to ask, Jester...does it fog when the heat is turned up and on defog, or when you're running the AC to defog? I had a Jetta (actually it was my wife's but she hated it so I ended up driving it most of the time) years ago that had an AC that got so cold it would send a fog out the vents.....I assume you'd have made this clear if it were happening.

 

One way you can have a fogging problem is when the drain for the ac evaporator gets plugged. When you select the windshield icon with the selector ****, the ac will run in order to dry the air regardless of the temp selected. If the if the water that condenses in the evaporator cannot drain, it gets blown through the heater core where it re humidifies the air then condenses again as fog on any cooler surface, like the windshield.

 

I've noticed in mine that it defogs better on cold than hot. It will defog slowly with the heat on however.