Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture LEMARK "LLB1014" - Not availableAUDI - A4, A3, TT, A6, S6; BMW - 3, 5; VW - Passat; MERCEDES-BENZ - C-Class, E-Class