Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture VEGAZ "ULS-688" - Not availableBMW - 7 (F01, F02, F03), X3, 3, 5, 1; AUDI - A4, TT; ALFA ROMEO - 156, Spider