A method and system for detecting an air leak in an engine

摘要

A system and method for detecting an air leak within an engine 12 is provided. The engine 12 includes an intake manifold 38 communicating with one or more combustion chambers 30 of the engine 12 and a controller 58 is provide to detect air leaks from the intake manifold 38 or a positive crankcase valve 61. The method, which may be embodied as executable code in a computer storage medium (84, 86, 88), includes measuring an exhaust gas constituent in exhaust gases from the engine 12 when the engine 12 is operating in an idle operating mode and further includes determining whether an air leak is present in the engine 12 based on a measured exhaust gas constituent, a first air-fuel correction value, and a second air-fuel correction value.