Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture Stark "SKLS-0140439" - Not availableBMW - 5 (E39, WB), 7 (E65, WB), 6, 3, 1; AUDI - A4, TT; MERCEDES-BENZ - C-Class