Patent ID: 7620489
Filing Date: 2009-11-17
Classification: F02D

Abstract:
1. Control method for the mixture ratio in a multi-cylinder internal combustion engine ( 1 ) equipped with at least two lambda sensors ( 7 ) placed upstream of a common catalytic converter ( 5 ) and at least two groups ( 9 ) of cylinders, each of which is associated with a respective lambda sensor ( 7 ), the control method comprising the steps of: establishing a mixture ratio target value; reading a first real value of the mixture ratio via a master lambda sensor ( reading a second real value of the mixture ratio via a slave lambda sensor ( calculating a first amount of fuel to inject into the cylinders ( the control method is characterized in that it comprises the additional steps of: calculating a target value for the mean of the second real value of the mixture ratio in a detection window; calculating the mean of the second real value of the mixture ratio in the detection window; calculating a correction value for the amount of fuel to inject in function of the difference between the mean target value and the mean of the second real value of the mixture ratio; and calculating a second amount of fuel to inject into the cylinders (