Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture NTK "91038" - Not availableAUDI - Q3, A3, A4, A1, A5; VW - Tiguan, Golf; SEAT - Leon, Ibiza; SKODA - Octavia, Kodiaq