| 摘要 |
<P>PROBLEM TO BE SOLVED: To more appropriately detect abnormal variation in an air-fuel ratio in a multi-cylinder internal combustion engine that can implement an air-fuel ratio feedback control. <P>SOLUTION: In a device for performing an abnormal variation detection process for detecting (S813) abnormal variation in an air-fuel ratio among cylinders based on variation in rotation when the amount of fuel injection is changed (S805, S829), and an air-fuel ratio feedback control process for correcting the amount of fuel injection for each of the cylinders based on feedback so as to make an air-fuel ratio for each of the cylinders follow a predetermined air-fuel ratio, the abnormal variation is detected (S811) with consideration of the corrected amount by the feedback correction in the variation abnormality detection process. The device can detect any abnormal variation in an air-fuel ration among the cylinders while maintaining regular operation thereof without facilitating a tendency to leave and save failure in the operation of an air intake system or a fuel supply system, thus allowing for more appropriate detection of variation abnormality. <P>COPYRIGHT: (C)2013,JPO&INPIT |
