| 摘要 |
An ECM 3 determines the occurrence of a failure and a failure site in a tumble control valve device 2 from a first failure diagnosis and a second failure diagnosis. According to the first failure diagnosis, a failure is determined to have occurred if a ΔTCV opening degree that represents the absolute value of the difference between a detected opening degree and a targeted opening degree of a valve body 4 is greater than a previously-set threshold a when the targeted opening degree of the valve body 4 is constant during a prescribed time T1. According to the second failure diagnosis, a failure is determined to have occurred if a ΔTCV opening degree that represents the absolute value of the difference between the opening degree of the valve body 4 when fully opened or the opening degree thereof when fully closed and the detected opening degree is greater than the previously-set threshold a when a portion rotating integrally with the valve body 4 has been pressed against a stopper 9 continuously for a prescribed time T2. |
