Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture Denso "DOX-2027" - Not availableAUDI - TT, A3, A4, A6, A8; SEAT - Alhambra, Ibiza; VW - Golf, Bora; SKODA - Octavia