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Oxygen Sensor: Description and Operation

DESCRIPTION AND OPERATION
The Heated Oxygen Sensors (HO2S) detect the oxygen content in the exhaust gas and signal the ECM (Engine Control Module). In operation, the ECM receives the signals from the sensor and varies the duration during which fuel is injected. To stabilize the sensor's output, the sensor has an internal heater. The Front Primary HO2S (Bank 2, Sensor 1) is installed in the front exhaust manifold, and the Rear Primary HO2S (Bank 1, Sensor 1) is installed in the rear exhaust manifold.