What Is Catalytic Converter?

An exhaust emission control device that converts toxic gases and pollutants in exhaust gas into less-toxic substances by catalyzing a redox reaction.

Located in the exhaust system between the engine and the muffler, it uses precious metals (platinum, palladium, rhodium) coated on a ceramic honeycomb structure to facilitate chemical reactions that convert carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) into carbon dioxide (CO2), water (H2O), and nitrogen (N2). A failing catalytic converter often triggers code P0420.