Diagnosis method for exhaust gas catalytic converter of internal combustion engine involves filling of oxygen reservoir, whereby diagnosis is done based on balance of oxygen entry and exit in reservoir and output signal of lambda probe

摘要

The method involves filling and emptying of oxygen reservoir (3), which is arranged in exhaust gas catalytic converter (1), by an upstream regulating mechanism (4), such that middle filling degree of oxygen is in permissible range. The diagnosis is based on the balance of entry and discharge of oxygen into oxygen reservoir and the output signal of lambda probe (5) in an internal combustion engine (2).