Originally Posted by focus_family
Pardon me if this sounds retarded..But if the car is out of time at all could that cause it?
Timing would cause erratic idle and driveability woes... behavior that would REALLY
get your attention! What you guys describe (o2 sensors that seemingly
'go bad') won't cause any weird behavior other that a CEL. The o2 sensor is a tattletale... that's it! If the exhaust gases go outside it's normal range; it raises a red flag (Check Engine Light).
It's just 'telling' you it's seeing some wonky data. The cause of which could be an internal oil leak or something else burning and creating abnormal gasses or excess amounts of the normal, run-of-the-mill stuff.