| 摘要 |
An EGR apparatus includes an EGR passage that connects an intake passage and an exhaust passage of an internal combustion engine in order to introduce a part of an exhaust gas into the intake passage, and an EGR valve for adjusting the amount of exhaust gas flowing through the passage. An oxygen concentration sensor that outputs a continuous value corresponding to the oxygen concentration of the exhaust gas flowing through the exhaust passage is provided in the exhaust passage. Valve-opening driving is performed on the EGR valve during fuel cut processing for halting the fuel supply of the internal combustion engine, and when a variation range of the output value of the oxygen concentration sensor accompanying the valve-opening driving is smaller than a predetermined value, it is determined that an abnormality is present in the EGR apparatus. |
