How much does it cost to replace oxygen sensors?
O2 sensors
£75-£200
How much could I save by replacing my own oxygen sensors?
Oxygen sensor replacement is normally a straightforward job. If your car has upstream and downstream O2 sensors, the latter tends to be more accessible and the job and should take a home mechanic under an hour. A main dealer can charge you up to around £150 an hour's labour to fit new O2 sensors, so this is a job well worth doing yourself, with a Haynes Manual by your side.