Abstract: Auxiliary control is used to reduce the processing load of an engine control computer by directly controlling a fuel injection system of an internal combustion engine. After initial set up, an auxiliary controller is able to control up to eight injectors while only receiving delay times from engine operating events, e.g. power stroke of each associated cylinder, and pulse width time periods defining the activation times for the injectors. The auxiliary controller can also maintain limited engine operation in the event of failure of the engine control computer when the computer is unable to provide updated delay times and pulse width time periods. A delay time and a pulse width time period are continuously calculated by the engine control computer and provided to the auxiliary controller. The most recently received delay time and pulse width time period are then used by the auxiliary controller to control up to eight identified fuel injectors.

Abstract: Air flow determination for an electronically controlled engine includes measuring air flow, determining a correction multiplier, correcting the air flow measurement, and determining if the correction multiplier needs to be updated.