hi every one
I have a 2007 Hyundai azera 3.8L V6.

My check engine light came on . OBD-II scan tool code of P0057 indicates Oxygen Sensor (bank 2, sensor 1) the sensor before the cat on the radiator side of the engine. I replace the o2 sensor with new one then i turn off the check engine light with the Scantool , but the check engine light come back on after 5 minutes. . Can anyone help me. Thanks

 

You changed the wrong sensor. P0057 is Bank 2 Sensor 2. That's the sensor after the cat:
OBD2-OBDII Engine Light Trouble Code P0057 HYUNDAI - HO2S 22 Heater Circuit Low | Engine-Codes.com

 

thanks novaresource i replaced the sensor bank2 sensor2 and my car now is very good

 

Hello Yousef and Thank You for posting with us..