Study on Misfire Diagnostic Strategy of On-Board Diagnostics System on LPG Passenger Car

This paper presents a method of misfire diagnostic detection on the LPG vehicle. The misfire rates of the catalytic converter irreversible damage temperature in full-working-condition and the misfire rates based on the exceeding OBD system emission limit in GB I test are respectively confirmed by Class A and B misfire diagnostic calibration experiments. The misfire diagnostic method in this paper is defined by calculating the engine roughness. The experimental results show that the proposed misfire diagnosis strategy is feasible and fully meets the requirements of the national standard.