Three Way Catalytic Converter (TWC), Checking: General Description
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A catalytic converter is a vehicle emissions control device that converts toxic pollutants in exhaust gas to less toxic pollutants by catalyzing a redox reaction (oxidation or reduction). Catalytic converters are used in internal combustion engines.
General recommendations
Oxygen sensors OK.
No leaks or damage to exhaust system.
Prior to repair work, perform a preliminary check to verify the condition. Refer to PRELIMINARY CHECK .