Is P0141 the Front or Rear Oxygen Sensor?

[EllianaLynn]

P0141 is the front oxygen sensor. In engines equipped with a three-way catalytic converter to reduce exhaust emissions, the oxygen sensor is an essential component. Since the purification capability of the three-way catalyst for CO, HC, and NOx drops sharply once the air-fuel ratio deviates from the theoretical value, an oxygen sensor is installed in the exhaust pipe to detect the oxygen concentration in the exhaust and send feedback signals to the ECU. The ECU then adjusts the fuel injection amount to maintain the air-fuel ratio near the theoretical value. The ECU determines whether the air-fuel ratio is too low or high based on the electromotive force difference from the oxygen sensor and controls the fuel injection duration accordingly.