pokeybritches, I can't say for sure about the first 15-20 seconds: I normally don't touch the throttle at all during that period of time and just allow the engine to idle. If it was doing it, it may not have enough effect for me to discern it.
I plugged the car into the OBDII reader again tonight, here are the screens.
Notice both lean and rich codes! And notice that it shows sensor #2 on both banks at 99.2%. I'm not sure what to think of that.
