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Home >> Nissan-Datsun >> 2021 >> Sentra SV >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System (1 Of 2) >> System Description >> Component Location >> Air Fuel Ratio Sensor 1 >> Component Description >> Description
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Component Description: Description

The A/F sensor 1 is mounted on the exhaust manifold, and transmits the signal of detected oxygen concentration in the exhaust gas to ECM.

G04875423Courtesy of NISSAN NORTH AMERICA, INC.

While O2 sensor changes output voltage by ON/OFF (rich/lean) mode within a narrow range of the stoichiometric ratio, the A/F sensor changes output voltage between 0 - 4 V for a wide range of air fuel ratio.

ECM judges the state of air fuel ratio with this signal, and precisely controls air fuel ratio to match the stoichiometric ratio. Also, the sensor is equipped with heater for maintaining the activated state.

G00575946Courtesy of NISSAN NORTH AMERICA, INC.