Heater Fan Leans Out Mixture???

[Glenn Lawton <lawtonglenn@gsmai.com>]

OK, so I've had a couple of days screwing around with
the urq and the new boost, and I saw something weird 
withe the Lean/Rich mixture gauge.

The gauge is by K&N, and is a series of fast blinking
LEDs to tell you what the mixture is. The curve is 
nonlinear, so the center 6 LEDs have higher resolution.
The gauge gets its signal from the stock OXS sensor,
and in normal driving you can watch the fast seek as
the OXS tries to keep the engine at stoich. 

When you hit the WOT switch, nearly all the lights
illuminate, including 1-2 Green RICH lights.

ANYWAY, if I turn on the heater fan to warm up the
cabin, the reading tends to LEAN, higher fan speeds
yeild more and more LEAN. Why????????????

Glenn