I have CEL 0305 and 0303... These are the O2 sensors front right and left heated O2 sensors... I do not know if they are bad or not but I have cleared the codes a few times and they keep coming back. Are these things cleanable??? I need to take care of this problem asap because I have inspection coming up... Thanks

 

If the codes keep coming back, I'd say it's about time to replace them. If the codes come up once and leave for a long time after you clear the codes, then they're still fine.

Not sure about cleaning them though, I think once the O2s are shot they're done, but I could be wrong.