Fuel System Monitoring: Notes
WARNING: This page does not describe the selected car, but rather 18 other vehicles, including the 2002 BMW Z8, 2002 BMW Z3, 2002 BMW X5, 2002 BMW M5, and 2002 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.
Fuel system monitoring is an OBD-II requirement which monitors calculated injection time in relation to engine speed, load, and the pre-catalytic converter oxygen sensor signals as a result of the residual oxygen in the exhaust stream. Engine control module uses the pre-catalyst oxygen sensor signals as a correction factor for adjusting and optimizing the mixture pilot control under all engine operating conditions.