Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture INTERMOTOR "64671" - Not availableSAAB - 9-3, 9-5, 9-3x; VOLVO - V70, S80; ALFA ROMEO - 156, 166; AUDI - A4, A3