Patent ID: 6993908
Filing Date: 2006-02-07
Classification: F02B,F02D,F02M,Y02T

Abstract:
1. A failure detection method implemented by a failure detection apparatus for an internal combustion engine, the failure detection apparatus including fresh air quantity detecting means for detecting a quantity of fresh air introduced into a combustion chamber of the engine, and a supercharger equipped with variable nozzles/vanes having a turbine and a compressor, the turbine being operated by an exhaust stream whose flow rate has been adjusted by the variable nozzles/vanes, to drive the compressor and thereby supercharge the engine with intake air, said failure detection method comprising: a target vane opening setting step of setting a target vane opening for the variable nozzles/vanes in accordance with an operating state of the engine such that an air-fuel ratio or excess air ratio of an exhaust system of the engine becomes equal to a predetermined value corresponding to the operating state; a vane opening control step of controlling the variable nozzles/vanes in accordance with the target vane opening set in said target vane opening setting step; a fresh air quantity reference value setting step of setting a reference value for the fresh air quantity in accordance with the operating state of the engine and the target vane opening set for the variable nozzles/vanes in said target vane opening setting step; and a failure detecting step of detecting abnormality of the fresh air quantity detecting means, based on a result of comparison between the fresh air quantity detected by the fresh air quantity detecting means and the reference value set in said fresh air quantity reference value setting step.