ON-BOARD DIAGNOSTIC METHOD AND SYSTEM FOR DETECTING MALFUNCTION CONDITIONS IN MULTIAIR (TM) ENGINE HYDRAULIC VALVE TRAIN

摘要

An on-board diagnostic system for detecting malfunction conditions in a hydraulic valve train of a MultiAir(TM) engine. The system comprises a plurality of pressure sensors for generating pressure signals located in a hydraulic circuit of the hydraulic valve train; and an engine control module for performing a waveform analysis of the pressure signals to detect malfunction conditions in the hydraulic valve train. The engine control module performs a frequency and/or time delay waveform analysis.