Device for detecting misfire of internal combustion engine equipped with double-ended coil and distributorless ignition system.

摘要

A misfire detecting device for a double-ended distributorless ignition system is provided. The device comprises a pulse generating circuit for generating a positive polarity pulse which is not so high as to cause spark discharge during the time after completion of spark discharge and before beginning of application of an ignition high voltage for next spark discharge, a reverse current preventing diode connected at an anode to an output end of the pulse generating circuit and at a cathode to a positive polarity side of a secondary winding of an ignition coil, a plug voltage dividing circuit for dividing a plug voltage between a center electrode and an outer or ground electrode of each of spark plugs to obtain a divided voltage therebetween, and a detecting circuit for detecting a misfire of the spark plugs on the basis of an attenuation characteristic of the divided voltage after application of the positive polarity pulse.