Method for operating combustion engine i.e. petrol engine, of vehicle, involves storing map using two operational parameters of combustion engine as input variables in engine control unit in which lambda probe controls air ratio

摘要

The method involves utilizing one of lambda probes (3, 5) for controlling air ratio using an engine control unit (7) depending on operation of a combustion engine (1). A map using two operational parameters of the combustion engine as input variables is stored in the engine control unit in which one of the lambda probes is used for controlling the air ratio. A three-path catalyst converter or four-path catalyst converter is used as an exhaust after treatment system (4). The lambda probes monitor efficiency of the exhaust after treatment system. An independent claim is also included for a combustion engine.