When does one know when to get new o2 sensors? I know from previous years when I used to frequent here more often that one of the things to do for better gas mileage might be having to change the o2 sensor.

Where could i get that done? Just at the local mechanic or somewhere like pep boys, or the Dealer?

How do I know when it should be time to change it?

 

If the o2 sensor is faulty, the check engine light will come on. If you run the codes and get p0140, po141 (02 sensors , bank 1 , sensor 2 and sensor 1), then you should replace the o2 sensors. If your check engine light is not on,then you really do not need to change.

 

not to thread jack, but I got one of those codes after I seafoamed my car. I just had autozone erase or resest the code(whatever they do). Would the code pop up again if I still have a problem or since I cleared it is there no way of telling if it really is faulty or was just messed up while the seafoam was cleanin everything?

 

If it's really a problem, it will come up again. If it doesn't, I wouldn't be too concerned.

 

It is very common to throw some misfire codes and or O2 codes during a seafoam. I did it yesterday on a friends car.