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

摘要

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.

主权项

1. A method, comprising:
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; 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; calculating, at the controller, a valve stuck index value based on the distinct portions of the MAP signal; and detecting, at the controller, one or more stuck valves of the engine based on the valve stuck index value and one or more thresholds.