Short Description

Short Description

Exhaust emission control system





Exhaust emission control comprises the following sub-systems:
^ Closed crankcase ventilation
^ Catalytic converters
^ Secondary air injection
^ Wideband lambda control

Lambda control, wideband
Unlike conventional lambda control with narrow band sensor, wideband lambda control can regulate the lambda value throughout the entire load and rpm range. The heated oxygen sensor measures the current lambda value and compares it with the requested value. If there is a deviation, the opening durations of the injectors are adjusted so that the requested and actual lambda values are the same. The advantages of wideband lambda control include the fact that ECM measures current lambda values throughout the entire load and rpm range, making a more precise dosage of fuel possible. Compared to narrow band control in which lambda control is deactivated when engine load is high, in this mode fuel is calculated based on a fuel matrix with correction for actual fuel adaptation. In addition, the EVAP canister can be purged within a broad range as lambda control is always active.