| 摘要 |
PROBLEM TO BE SOLVED: To favorably remove NOx by securing an opportunity at which rich control is performed.SOLUTION: A NOx storage catalyst 14 is arranged in an engine exhaust passage. When it is determined that a rich control execution condition is established, rich control is performed for discharging NOx or SOx from the NOx storage catalyst. When it is determined that the rich control execution condition is not established, a gear position at which the rich control execution condition is established is obtained as a target gear position assuming that a gear position of a transmission 25 is changed under a constant engine output. An indication indicating that the gear position should be changed to the target gear position is displayed to a vehicle driver by an indicator 27. When the gear position is changed to the target gear position by the vehicle driver, and it is determined that the rich control execution condition is established, the rich control is executed. |
