There are several oxygen sensors, but either way, go to http://www.alldatadiy.com/
or http://www.bentleypublishers.com/ and get a repair manual. This can save you a lot of time and money, and it will help you with the next repair you decide to do.
this job is no picnic! a special socket is needed and depending on which sensor, maybe a box of band-aids. unless you can replace easy stuff like brakes,oil,etc i'd keep paying for replacement of sensor as the prefered option. no offense intended.
...Diagnostic report says" Catalyst system efficiency below threshold bank. Last year one of the oxygen sensors was removed when my engine light came on. Is the engine light now due to the catalytic conve...