Engine misfire detection method and device and engine

The invention belongs to the technical field of engines, and particularly relates to an engine misfire detection method and device and an engine. The engine misfire detection method comprises the following steps of acquiring a real-time exhaust pulse characteristic value of a target cylinder of the engine; calculating the ratio of the real-time exhaust pulse characteristic value to the stored exhaust pulse characteristic value of the target cylinder; and judging that the target cylinder is in a misfire state according to the fact that the ratio is smaller than a preset ratio. According to the engine misfire detection method, the real-time exhaust pulse characteristic value of the target cylinder of the engine is obtained firstly, then the exhaust pulse characteristic value stored in the engine is obtained, and it is judged that the engine is in the misfire state according to the fact that the ratio of the real-time exhaust pulse characteristic value to the stored exhaust pulse characteristic value is smaller