Hi guys, my car had a check engine on for some time now. I had it scanned today, and this is the code that came up:
2AD2 Oxygen Sensor after catalytic converter dynamic response in overrun.


Any thoughts?

 

How many miles on your car? What car do you have? Sensors eventually go and need to be replaced. If you do change it out stick with OEM.

 

I should have lead with that
2008 Justa, 200,000 km.

 

If those are original sensors you did well.

 

which sensors?

 

I suggest replacing the o2 sensor, the one past the cat..

 

I thought the downstream O2 didn't do much.

 

Replace the o2 sensor. They do go bad and are easy to replace.

 

The ECU compares the output of the pre- and the post-cat sensors to make decisions on fuel & air metering. So they're both important. If the error code indicates a problem with the sensor, and not with something in your fuel or air (like a fugitive leak), then you should just change them out.

Your error code seems to indicate a problem with the sensor itself, so, yes, change it, or better yet, change both. At 200,000km, you've gotten about 40,000 more kilometers more than they're rated for. Consider that a win.