Patent ID: 6941936
Filing Date: 2005-09-13
Classification: F02D

Abstract:
1. A control system for an internal combustion engine having at least one control device that affects an air-fuel ratio of an air-fuel mixture to be supplied to said engine, said control system comprising: an air-fuel ratio sensor provided in an exhaust system of said engine; air-fuel ratio correction coefficient calculating means for calculating an air-fuel ratio correction coefficient for correcting an amount of fuel to be supplied to said engine so that the air-fuel ratio detected by said air-fuel ratio sensor coincides with a target air-fuel ratio; air-fuel ratio affecting parameter calculating means for calculating an air-fuel ratio affecting parameter indicative of a degree of influence that an operation of said at least one control device exercises upon the air-fuel ratio; correlation parameter calculating means for calculating at least one correlation parameter which defines a correlation between the air-fuel ratio correction coefficient and the air-fuel ratio affecting parameter using a sequential statistical processing algorithm; learning means for calculating a learning correction coefficient relating to a change in characteristics of said at least one control device using the at least one correlation parameter; and air-fuel ratio controlling means for controlling the air-fuel ratio using the air-fuel ratio correction coefficient and the learning correction coefficient.