| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a valve timing adjustment system preventing the unlocking failure and locking failure of a vane rotor. <P>SOLUTION: In S102, when it is determined that time difference between first time when an instruction for setting intake valve opening/closing timing as desired opening/closing timing is input into an ECU and scheduled time when hydraulic pressure is adjusted by a pressure regulating valve is smaller than predetermined time, pressure of oil before and after adjustment by the pressure regulating valve is calculated as hydraulic pressure before adjustment and hydraulic pressure after adjustment, in S103. Next, in S104, it is determined whether the hydraulic pressure before adjustment is lower than start failure lower limit hydraulic pressure P1. Then, in S105, it is determined whether the hydraulic pressure after adjustment by the pressure regulating valve is lower than start failure upper limit hydraulic pressure P2. When it is determined that the hydraulic pressure before adjustment is lower than the start failure lower limit hydraulic pressure P1 and the hydraulic pressure after adjustment is lower than the start failure upper limit hydraulic pressure P2, the scheduled time for adjusting the hydraulic pressure is delayed by the predetermined time with respect to the first time, in S106. <P>COPYRIGHT: (C)2013,JPO&INPIT |
