Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture OSSCA "33600" - Not availableBMW - 3 (F30, F80), 1, 4 (F32, F82), 2, 5, X3, 6, X4; BMW (BRILLIANCE) - 3 Series