| 摘要 |
PURPOSE:To perform the accurate judgment of a knock detecting means at all times by changing a sensor fail judging level according to valve timing and/or lift, in a device which is equipped with a variable valve timing mechanism and a knock controlling means. CONSTITUTION:In an internal combustion engine 10 provided with two intake and exhaust valves 54, 56 at each cylinder, a variable valve timing mechanism 60, controlling valve timing and lift of these intake and exhaust valves 54, 56, is connected to these valves 54, 56. In addition, when a knock sensor has detected knock occurrence, an igniter 62 is controlled so sa to compensate ignition timing for its timing delay by the control unit 52. In this case, in the control unit 52, there is provided with a fail judging means which performs a trouble judgment of the knock sensor 44 in comparing output of the knock sensor 44 with a specified fail judging level. Then, the fail judging level is made so as to be changed according to the valve timing and/or lift. |
