Patent ID: 7168410

Claim:
An idle speed controller for executing idle speed control for an internal combustion engine including an intake valve and an exhaust valve, the idle speed controller comprising: either one of an intake variable working angle mechanism for variably setting an working angle of the intake valve and an exhaust variable working angle mechanism for variably setting an working angle of the exhaust valve; a variable valve timing mechanism for variably setting valve timing for the intake valve; and an electronic control unit for executing idle speed control; wherein when the internal combustion engine is idling and an advancement failure of the variable valve timing mechanism occurs thereby advancing the valve timing of the intake valve from an intended timing, the electronic control unit performs idle-up during execution of the idle speed control to increase a target idle speed; and wherein when the working angle set by either one of the intake and exhaust variable working angle mechanism is less than a predetermined value, the electronic control unit changes an increase amount of the target idle speed to a lower value if an advancement failure occurs when performing the idle-up as compared to when the working angle is greater than the predetermined value.