Systems and methods for diagnosing valve lift mechanisms and oil control valves of camshaft lifting systems

摘要

A system for diagnosing a switchable roller finger follower (SRFF) and an oil control valve (OCV) comprises a signal monitoring module and a fault detection module. The signal monitoring module receives a single cylinder fuel correction signal (ICFC signal) and / or an air / fuel ratio imbalance signal (AFIM signal) when: an engine speed signal is within a predetermined range of speed; an engine load signal is in a predetermined range of a load; and an activated carbon can vapor signal is in a predetermined range of a flow rate. The fault detection module detects a fault of an SRFF and / or an OCV based on an exhaust gas recirculation value and the ICFC and / or the AFIM signal. The ICFC and AFIM signals are generated based on: an engine position signal; and an oxygen signal and / or a wide-range air-fuel signal.