| 摘要 |
PROBLEM TO BE SOLVED: To suppress change of the contact state of exhaust gas to an air-fuel ratio sensor with change of an exhaust flow rate, improve detection accuracy and suppress erroneous detection.SOLUTION: When executing determination of air-fuel ratio imbalance between cylinders, a WGV 27 is opened, and the opening of the WGV 27 is controlled on the basis of an exhaust flow rate. According to the exhaust flow rate, the contact state of exhaust gas to an air-fuel ratio sensor is induced to a state suitable for detection, and change of a mainstream position according to the exhaust flow rate is compensated or suppressed by utilizing the WGV 27. Change of the contact state of exhaust gas to the air-fuel ratio sensor 17 with change of the exhaust flow rate is suppressed, detection accuracy is improved, and erroneous detection can be suppressed. |
