Control circuit identifying misfiring of IC engine - analyses misfire signals to determine degree of misfire and adjust fuel injection

摘要

The i.c. engine is fitted with a detection system for each cylinder to monitor the ion current from the spark plug discharge. The ion current is analysed to determine if a misfire has occured and to what degree. The processor separates genuine misfires from partial misfires, which still provide a spark, and from error signals attributed to noise etc. in the sensing circuit. The genuine misfires result in a cut-off in the fuel feed to the respective cylinder. The system generates a misfire signal if the ion current is below a set level. This signal is incremented and analysed. The peak signal as well as the incremental signal is measured to determine if the misfire is total. The fuel feed can be totally cut off or reduced by a programmed amount. ADVANTAGE - Even running; improved engine control.