thank alot Hoser is it hard to do on the left sidehoser said:When an 02 sensor goes bad, many vehicles go into "limp" mode where the air/fuel mixture will be fixed often towards a richer than optimal fuel mixture. Bad 02 sensors can cause poor emissions, reduced power, increased fuel consumption and can lead to catalytic converter failure (overheat).
An independent shop will be cheaper than the dealer. Doing it yourself would be cheapest and is easy, as long as you can access it. I would only use OEM parts. After the part is installed, it can take up to 50 miles to be fully back on track. Drive it a bit if you have to pass a smog test.