Should both O2 sensors be replaced at once?

[Chris Boddum]

Hi 

I recently had the code for the pre-cat O2 sensor light up my check engine light. Would it be preferred that both sensors are replaced at once (both before and after cat), or is it enough to just replace the sensor that is showing a fault? I don't want it to light up again because the two sensors are no longer worn the same. Thanks!
 

[flash22]

no need to change both but do use a quality sensor, OEM is Bosch - The pre cat is known as an air fuel ratio sensor

https://www.ebay.co.uk/itm/334120192615

[Chris Boddum]

16 minutes ago, flash22 said:

no need to change both but do use a quality sensor, OEM is Bosch - The pre cat is known as an air fuel ratio sensor

https://www.ebay.co.uk/itm/334120192615

Perfect, thank you! Is it just plug and play, or do I need to reset the ECU like on some cars?

[flash22]

it should clear the code after 5 mins of start/drive if not clear the codes otherwise it's a simple swap