VARIABLE VALVE LIFT DIAGNOSTIC TECHNIQUES USING AN INTAKE MANIFOLD ABSOLUTE PRESSURE SIGNAL

• Main Authors: GEBBY BRIAN P, WU ZHIJIAN JAMES
• Format: Patent
• Language: English
• Published: 18.06.2015
• Subjects: BLASTING; CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TOTRANSPORTATION; COMBUSTION ENGINES; CONTROLLING COMBUSTION ENGINES; CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES; ENGINE PLANTS IN GENERAL; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE; WEAPONS

A method can include receiving, at a controller for an internal combustion engine, the controller having one or more processors, an intake manifold absolute pressure (MAP) signal indicative of an air pressure in an intake manifold of the engine. The method can include processing, at the controller, the MAP signal in a crank angle domain to obtain distinct portions of the MAP signal corresponding to cylinders of the engine, respectively. The method can include calculating, at the controller, a valve stuck index value based on the distinct portions of the MAP signal. The method can also include detecting, at the controller, one or more stuck valves of the engine based on the valve stuck index value and one or more thresholds.