Diagnostic system and method for detecting internal combustion engine faults using exhaust pressure readings
AssigneesTula Technology, Inc., Cummins Inc.
InventorShikui Kevin Chen
Life of this patent
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Abstract
A diagnostic system and method that (a) that uses models indicative of both successful firing and skips to determine if cylinders of a skip fire controlled internal combustion engine have successfully fired or successfully skipped and (b) uses filtered exhaust gas pressure readings for detecting faults associated with EGR systems and/or turbocharger systems.
Claims30
A method, comprising:
- ascertaining if a cylinder of an internal combustion engine is commanded to fire or skip during a cylinder event;
- comparing a measured exhaust pressure, associated with the cylinder event, with either:
- (a) a first exhaust pressure threshold indicative of a successful or unsuccessful skip if the cylinder is ascertained as commanded to skip;
- (b) a second exhaust pressure threshold indicative of a successful or unsuccessful fire if the cylinder is ascertained as commanded to fire;
- and
- determining if the cylinder successfully skipped as commanded or successfully fired as commanded during the cylinder event based on the comparison of (a) or (b) respectively.
An engine control system configured to control operation of an internal combustion engine (ICE), the engine control system configured to:
- (a) command cylinders of the ICE to skip during first cylinder events and fire during second cylinder events;
- (b) compare first measured exhaust pressures associated with the first cylinder events to a first exhaust pressure threshold indicative of an unsuccessful skip respectively;
- (c) compare second measured exhaust pressures associated with the second cylinder events to a second exhaust pressure threshold indicative of an unsuccessful fire respectively;
- and
- (d) generate fault flags when the cylinders unsuccessfully skipped and unsuccessfully fired as commanded based on the comparisons of (b) and (c) respectively.
A fault detection method comprising setting a diagnostic fault flag if a filtered exhaust pressure signal, measured over multiple cylinder events of an internal combustion engine, falls below a threshold exhaust pressure.
Dependencies are inferred from the claim text.