i suspect its stalling cos youve removed the AAC valve
i just cant see how the engine will idle with the valve removed
the valve bypasses air into the plenum around the throttle body when its closed
if you dont bypass or let air in when the throttle body is closed, the engine is basically starved of air and will stall
the 02 sensor control and closed loop function runs and checks 02 feedback from the sensors
in runs in loops and also the 02 sensors need to be heated up, they dont just work
they must be warm, so they have a heater control system in them to heat up and stay warm
this runs periodicially, which is when the 02H circuit relay comes on
its prefectly normal for the 02 sensors to be peridoicially heated up in cycles so thats not a problem
why its making it richen up off the planet im not sure i suspept a wiring fault or something
if the signal to the FC from the 02 sensors is scrambled / out of range when it runs in closed loop
it might keep trying to lean out too much and basically makes it richen up
check the 02 co-efficient in datalogit, has someone changed it?
if its wrong the FC will try and aim for an AFR out of range (like what yours is doing)
from memory the 02 co-efficient in datalogit should be like 1.047 or something like that
unplug the sensors, turn 02 feedback off
then fix your stalling issue