Oxygen, Lambda Sensor Exhaust Oxygen Sensor (O2 Sensor) Measures oxygen in the exhaust so the ECU can correct the air-fuel mixture LEMARK "LLB530" - Not availableFORD - Focus, Mondeo, Kuga, S-MAX; SAAB - 9-3, 9-5; VOLVO - C70, S60; PORSCHE - 911