Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture FREY "880613001" - Not availableBMW - 3 (F30, F80), 5, 4 (F32, F33, F82), 1, 2, X5, X1, X3, X4, Z4 Roadster, 6, 7, X6