Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture VDO "A2C59513321Z" - Not availablePEUGEOT - 405, 406, 306, 407, 106; CITROËN - ZX, Xsara; FIAT - Ducato, Ulysse