Fuel System Monitoring: Notes
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2001 BMW Z8, 2001 BMW X5, 2001 BMW M5, 2001 BMW 750iL, and 2001 BMW 740iL. 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.