Testing the Effectiveness of the Misfire Detection System

Abstract

A methodology to analyse and predict the behaviour of the current misfire detection system & algorithm is presented with special focus on the effects and contribution of the noise contributed mainly by the variation in driveline configuration. The existing line up of CNG engines are used to compare the performance of the simulating model with the real time functioning of the system. Two distinct diesel vehicle models with known and reported significantly varying driveline disturbances are investigated along with the developed model of the system. Sufficient tolerance band coupled with accurate algorithms in the existing misfire detection system have been a key advantage providing the opportunity to extend the same system across future possible vehicle variants in spite of noise contributions. A misfire generating system designed and built with the possibilities to induce and generate misfires at controlled rate in order to assist real time evaluation of the detection system and diagnostics performance is also presented. A comprehensive study from available literatures in the automotive research industry carried out to determine possibilities to improve the existing misfire detection system and algorithm resulted in identification of usage of a viable alternate detection system as an assisting contribution to the current algorithm.