Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture BOSCH "0 281 004 071" - Not availableAUDI - A4, A3, A5, A6, S6; RENAULT - Megane; BMW - 1, 3; ALFA ROMEO - 159, 147