Misfire detecting system for internal combustion engine

摘要

In a system which detects a misfire in an internal combustion engine, the detected value (17) of the sparking voltage at a plug (16) is compared (5b) with a first set value (Vmis1) and the degree to which the detected value of the sparking voltage exceeds the first set value is measured. This is compared (5b) with a second set value set in dependence on detected values of operating parameters of the engine. It is determined based upon results of the latter comparison whether or not a misfire occurred in the engine is in a set operating condition.