It is possible that your brand new thermostat is bad, though it's a pretty low-incidence hit.

And quit bragging. :-) If you can afford a 996, you can afford another thermostat; grab one from someplace else, and swap it in again.

 

I get it from Carson Oil, They always have it in stock at the Prineville Location.



http://www.carsonoil.com/default.asp

 

OK, it is done and it is working perfect. No more auxiliary fan no matter how long it idles and the heater is working fine. Here are some pix:

Lower Hose:
(BMW E46 Hose I had sitting on the shelf.)



Upper Hose:
(Some hose I got from PepBoys.)



If you do this, don't forget to drill a small bypass hole in the thermostat.