| 摘要 |
PROBLEM TO BE SOLVED: To sense the state that an ion current cannot be properly detected in spite of the normal combustion of mixture in a cylinder.SOLUTION: A control device estimates that there is a trouble in detecting the ion current flowing in the electrode of an ignition plug, only when determining that combustion in the cylinder is stable resulting from the determination of a combustion state referring to the reduced amount of the revolving speed per predetermined revolving angle of an internal combustion engine, although determining that the combustion in the cylinder is instable or misfired resulting from the determination of the combustion state referring to the ion current flowing in the electrode of the ignition plug during the combustion of the mixture. |
