Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture OSSCA "33599" - Not availableBMW - 5, 3, X3, 7 (F01, F02, F03), 1, 6, X5, Z4, X1, X6; BMW (BRILLIANCE) - 5 Series