BMW 325Li 2019 Model 2.0T Rear Oxygen Sensor 11788651104, more accurate exhaust monitoring

BMW 325Li 2019 2.0T rear oxygen sensor (OEM 11788651104) installed behind the catalytic converter; monitors exhaust oxygen content and provides feedback to the ECU to adjust air-fuel ratio for emissions compliance. Fits this model; installation difficulty medium; about 1 hour; avoid damaging threads during removal. If fuel consumption rises, acceleration is weak, check engine light on, or emissions exceed standards, sensor signal is abnormal and should be replaced promptly.