Patent ID: 7607345

Claim:
A misfire detection apparatus for an internal combustion engine that detects a misfire in the internal combustion engine provided with a flywheel damper based on a rotation fluctuation of the engine, wherein an operation range where misfire detection is affected by said flywheel damper is set in advance, the misfire detection apparatus for the internal combustion engine comprises: a determination portion determining whether or not an operation state of said internal combustion engine is within the operation range affected by said flywheel damper; a detection control portion restricting misfire detection, when the operation state of said internal combustion engine is within the operation range affected by said flywheel damper; and a total misfire counter and a cylinder-by-cylinder misfire counter, wherein a count value of said total misfire counter and a count value of said cylinder-by-cylinder misfire counter are both updated, when the operation state of said internal combustion engine is outside the operation range affected by said flywheel damper, and only the count value of said total misfire counter is updated, when the operation state of said internal combustion engine is within the operation range affected by said flywheel damper.