| 摘要 |
The occurrence of an error in a measured value of a sensor due to an additive agent added into an exhaust gas is suppressed. Provision is made for detection means that is arranged in an exhaust passage of an internal combustion engine for detecting a state of the exhaust gas, addition means for adding the additive agent into the exhaust passage, a catalyst that is arranged at the downstream side of the detection means and the addition means so as to receive a supply of the additive agent from the addition means, determination means for determining whether detection accuracy of the detection means drops due to the additive agent to be added from the addition means, and stop means for stopping detection of the state of the exhaust gas by the detection means in cases where it is determined by the determination means that the detection accuracy of the detection means drops. |
