Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture ACI-AVESA "SLS-13305" - Not availableCITROËN - ZX, XM, AX, C15, Jumper; PEUGEOT - 405, 306; FIAT - Ducato, Ulysse