Yukon 2WD V8-5.7L VIN R (1997)
Oxygen Sensor: Description and Operation
Heated Oxygen Sensor (HO2S) Cutaway
OPERATION
In order to control emissions of Hydrocarbons (HC), Carbon Monoxide (CO) and Oxides of Nitrogen (NOx), a three-way catalytic converter is used. The
catalyst within the converter promotes a chemical reaction which oxidizes the HC and CO present in the exhaust gas, converting them into harmless
water vapor and carbon dioxide. The catalyst also reduces NOx, converting it to nitrogen. The VCM has the capability to monitor this process using
HO2S 2. HO2S 2, located in the exhaust stream past the three-way catalytic converter, produces an output signal which indicates the oxygen storage
capacity of the catalyst; this in turn indicates the catalyst's ability to convert exhaust emissions effectively.