Do o2 sensors go out in pairs?
My friends max threw a code for the right uppper bank o2. replaced that then it threw a code 2days later for the left bank o2 sensor.
I guess it can be expected due to age and if one went bad figured the other one would also. It went bad a few weeks after getting the GReddy SP exhaust installed.
Can someone clarify this for me? Also would it make a huge difference in getting a bosch sensor opposed to a oem sensor? If so what..

 

I think OEM is Bosch. That is what I used when I replaced mine. I've had them in for 4 months now with no ploblems.

Troy

 

Why you have to replace the O2 censor? I was reading the forum and I had vibration and missed Idle. I changed one bad ignition coil and the car is still not on par. Some one suggested to change O2 censor. Would like to know what will be benifit for changing O2 censor. I have 99 GLE with 60K. If change do I need 2 or 1 ? Pleaase advice. Thks.