Α 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 CON. Αn 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.
Catalytic converter failures generally fall in the category of physical damage or catalyst failure. Physical damage usually can be visually identified – cracks, dents, etc. Internally, the structure can be cracked, broken, or melted. Where high heat may have lead to catalyst failure, the engine and related systems need to be thoroughly checked.