Patent ID: 6666200
Filing Date: 2003-12-23
Classification: F02D

Abstract:
A method for controlling an air/fuel ratio of an engine, such engine being supplied fuel from a fuel injection system to inject fuel into a cylinder of such engine, such method, comprising:providing a model of the engine, such model representing a relationship between: (1) a signal model representative of estimated air/fuel ratio of the engine relative to a stoichiometric air/fuel ratio for the engine; and, (2) fuel injected into the cylinder of the engine; measuring exhaust gas oxygen emission from the engine during operation of such engine; producing as a function of such measured oxygen, an actual signal representative of the actual air/fuel ratio of the engine relative to a stoichiometric air/fuel ratio for the engine produced by such engine during operation of such engine; comparing the actual signal with the signal model provided by the model in response to fuel injected into the engine to produce a model error signal; adjusting the fuel injected into the engine in accordance with the model error signal.