Misfire-Fault Classification for Future On-Board Diagnostics III Vehicles

Current OBD-II vehicle systems detect misfires by monitoring slight variances of crankshaft acceleration throughout power-strokes of each of the engine’s cylinders. If the PCM determines that the acceleration of the engine’s crankshaft is inappropriate, it concludes a misfire is detected. However, a...

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Bibliographic Details
Main Author: Suda, Jessica Lynn
Format: Others
Published: OpenSIUC 2018
Subjects:
Online Access:https://opensiuc.lib.siu.edu/theses/2372
https://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=3386&context=theses
Description
Summary:Current OBD-II vehicle systems detect misfires by monitoring slight variances of crankshaft acceleration throughout power-strokes of each of the engine’s cylinders. If the PCM determines that the acceleration of the engine’s crankshaft is inappropriate, it concludes a misfire is detected. However, after this misfire is detected, the technician still needs to diagnose (isolate) the root-cause. Diagnosis is no easy task, especially with several potential subsystems that could be at fault: fuel injection, air-intake, sparkignition, and engine-mechanical. With this being said, it is difficult for many technicians to isolate the fault causing a misfire because of the wide range of root-cause possibilities within each of the subsystems. The proposed On-Board Diagnostics III contributes to the computer-aided detection and diagnosis of future-production vehicle faults. Several data-mining algorithms were investigated and applied to data parameters collected from misfire and misfire-free fault instances. Rules were then used to accurately classify future engine misfire fault instances.