Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture FEBI Bilstein "175840" - Not availableCITROËN - C3, C5, Xsara, C2, Saxo; PEUGEOT - 206, 207; FIAT - Fiorino, Qubo