Catalytic Converter
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A Three-Way-Catalytic (TWC) converter is used to reduce exhaust emissions. This type of converter can reduce hydrocarbons (HC), carbon monoxide (CO) and oxides of nitrogen (NOx).
The upstream section of the converter contains a reducing/oxidizing bed to reduce NOx while oxidizing HC and CO. An air supply pipe from the air injection system injects air between the beds of the converter. Thus, the second converter bed oxidizes any remaining HC and CO to efficiently reduce exhaust emissions.