My girl has an 03 Mitsubishi outlander...her sel came on and we got it checked it was a bad o2 sensor...this morning then light never came on

Is it possible the o2 sensor unclogged itself? Or some other phenomenon lol

And the code was never cleared by the way lol

 

Just cause you got it scanned and the code said "O2 sensor circuit fault" does not mean the sensor is bad... It could mean there is some crud in the plug on it somewhere along the line too thats causing poor communication with the sensor, a wire rubbed through, or some other connection problem.

Its time you get underneath and rule that stuff out first. The sensor is probably a post-cat sensor, so look at the one after the cat. Look for the wires touching the exhaust pipe, or maybe yanked on by snow or grass or something.

 

naturally she doesnt keep track of her mpg (typical female lol) so i guess ill have to take a look next time shes over. she only has two on her suv i wish the guy told us what bank/sensor it was.

i will have to check the post cat, thats probably the easier one to get to

thank you for the info ohsofly!!

 

I've had random codes come on once and never come back before. What I usually do, now, is to clear any code the first time it shows up, as long as the vehicle isn't exhibiting any symptoms. If it comes back, then it's time to check it out. But several times I'll clear it out, and it never resurfaces.

Now, I'm not saying to ignore any potential problems, but it seems like sometimes a system will be out of range just enough, for just long enough, to set a code, even if nothing is wrong.

 

yea ill assume if it doesnt come back on it was fluke lol, but if it does ill have the code read and actually get the bank/sensor noted. next times she over i still wanna check the wires to make sure they arent touching the exhaust or another hot component