Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture DRiV "OPH044" - Not availableBMW - 3, 5, 7 (E65, E66, E67), 1, 4; AUDI - A4, A3; ALFA ROMEO - 156, 159