Rear Catalyst Monitor Oxygen Sensor
DESCRIPTIONUse a three-way catalytic converter in order to control the emissions of the Hydrocarbons (HC), the Carbon Monoxide (CO), and the Oxides of Nitrogen (NOx). The catalyst within the convener promotes a chemical reaction which oxidizes the HO and the CO that is present in the exhaust gas, converting the HO and the CO into a harmless water vapor and carbon dioxide. The catalyst also reduces NOx, convening the NOx to nitrogen.
OPERATION
The ECM has the ability to monitor this process by using the Bank 1 HO2S 2 and the Bank 2 HO2S 2 heated oxygen sensors. The front HO2S sensors produce an output signal which indicates the amount of oxygen present in the exhaust gas entering the three-way catalytic converter. The rear HO2S sensors produce an output signal which indicates the oxygen storage capacity of the catalyst. This in turn indicates the catalyst's ability to convert the exhaust gases efficiently. If the catalyst is operating efficiently, the front sensors will produce a far more active signal than that produced by the rear sensors.