So I finally got my O2 sensor off, without stripping the thread. Popped the new one in, and nothing happened. Still have the same Service Engine light on. Does it take awhile to kick in or is it possible they messed up at autozone when they read the codes, or something else I've overlooked?? I have a 99 SL2.

 

unplug the negative terminal for 15 minutes. And your cel should go off.