Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture VEGAZ "ULS-389" - Not availableBMW - 3 (E91, E92), 5, 1 (E81, E87), 6, Z4, X3, 7 (F01, F02, F03), X1, X5