Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture FREY "880609201" - Not availableBMW - 3 (F30, F80), 5, 1, 4 (F32, F33, F82), X3, X1, X5, Z4 Roadster, 2, X4, 6, 7, X6