Misfire detection apparatus of internal combustion engine

摘要

A misfire detection apparatus of an internal combustion engine for detecting combustion or a misfire of an air fuel mixture in the internal combustion engine based on an ion current generated at the combustion time of the air fuel mixture. The misfire detection apparatus includes ion current detection means and misfire determination means. The ion current detection means detects the ion current responsive to the amount of ions occurring in a cylinder just after combustion of the air fuel mixture in the cylinder in the internal combustion engine. The misfire determination means calculates a predetermined function based on the ion current detection value and determines that the condition is combustion when the magnitude exceeds a threshold value.