Lexus Rear Oxygen Sensor 89465-48340 Catalytic Efficiency Precise Monitoring

Lexus downstream oxygen sensor (OEM 89465-48340) installed downstream of the exhaust catalyst; real-time monitoring of exhaust oxygen content to assess catalytic converter efficiency and feed data to the ECU to correct the air-fuel ratio. Fits ES350, RX350, GS350 and other models with 2GR-FE or 2GR-FSE engines. Installation difficulty is medium; labor about 0.5–1 hour; avoid thread damage during removal. If the engine fault light is on, catalytic efficiency may be abnormal or sensor signal deviates; replacing restores accurate monitoring.