Detecting leaking exhaust valve of vehicle

摘要

A measure of the rough running of an engine is formed using a suitable device and air is fed into the region after the exhaust vale in the flow direction of the engine's exhaust gases. A first measure (LU1) of the running roughness of the engine is obtained without air fed into the above region and a second measure (LU2) obtained with air fed in. An exhaust valve is detected as leaking when the first and second measurements differ by more than a defined amount consistent with smooth running. The method may be implemented in certain engine operating states.