Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture DRiV "OPH057" - Not availableAUDI - A4, A6, TT, A3, A8; VW - Passat, Golf; BMW - 3, 5; ALFA ROMEO - 156, 166