Catalytic Converter

The catalytic converter reduces the carbon monoxide (CO) and hydrocarbons and nitrogen oxide (NO)/nitrogen oxides (NOx) content of the exhaust gases. In the catalytic converter the exhaust gases pass through honeycombed ceramic elements whose surface is treated with a special deposit of washcoat containing catalytic elements. The washcoat also increases the surface area of the ceramic elements by a factor of approximately 7, 000.

The washcoat contains Palladium and Rhodium. They both facilitate the oxidation of CO and hydrocarbons, accelerating their reaction with oxygen (O2) to produce carbon dioxide (CO2) (if CO) and CO2 and H2O (if hydrocarbons). The washcoat also facilitates the reduction of the nitrogen oxides into molecular Nitrogen (N2) by extraction of oxygen from the NOx molecules. The mechanics of Oxidation of CO hydrocarbons and reduction of NOx occurs according to the level of oxygen in the exhaust flow (lambda control). Maximum efficiency (best CO/hydrocarbons oxidation, best NOX reduction) occurs at lambda 1.

Each HO2S  is used to monitor the exhaust gases leaving the engine. The Powertrain Control Module (PCM) uses the information from the HO2S  to provide accurately measured quantities of fuel to the combustion chambers. The PCM  uses the information from the HO2S  to minimize the exhaust emissions.

For additional information, refer to: ELECTRONIC ENGINE CONTROLS - INGENIUM I4 2.0L PETROL/INGENIUM I4 2.0L PETROL - PHEV (G2270401) .