The O2's have 131,000 on them and car idles rough, I checked them with a scanner and they "bounce around" indicating they are good, but I have heard people that changed them even though they appeared good per the scanner and the idle improved?? Is this true? Help?

 

Are they "bouncing" slow or real fast?
O2s can slow down and not give a good reading to the PCM.
At your mileage I would change them regardless.

 

anyways.