Abstract: A method and apparatus for executing a strategy of electronic throttle monitoring of a powertrain system including an electronic powertrain control module, and an electronic throttle control, includes an independent processor receiving signals shared with the powertrain control module from sensors and actuators on the vehicle. The monitor operates in a monitoring mode to detect faults occurring in the powertrain or the powertrain control module, and determines whether mitigating conditions occur in conjunction with detected power output greater than power demand. In the event that these mitigating conditions are not detected, the monitor operates in a limiting mode to actuate decreases in power output below the level of power demand.

Abstract: An air/fuel control system (8) and method to maintain the air/fuel ratio of each engine bank (28) out of phase with one another. A feedback variable is generated (410-428) in response to a comparison of a difference in exhaust gas oxygen sensors (44, 55) from respective left and right engine banks (56, 57) to a reference (104-120). Separate feedback variables are generated for each engine bank by phase inverting the feedback variable between the banks and adding an adjustment signal (450-462). The adjustment signal is generated from a PI controller responsive to a comparison of the sum of the left and right exhaust gas oxygen sensors (44, 55) to a reference (440-448).