Depends on what car you have, but it will probably cost you about 400$ or more.
$300 with labor
It just cost me $220.00
A Bosch O2 sensor, from NAPA, is $91 here in southwest Washington.
To change an O2 sensor you need to disconnect the wiring harness from the sensor. Use an O2 sensor socket and ratchet set to remove the old sensor and replace with the new one.
An O2 sensor unscrews just like a spark plug.
the price of the 02 sensor. under 20 bucks. and about 10 min of your time.
Remove the vacuum hose from the O2 sensor. Remove the wiring harness. Remove the O2 sensor retaining screws. Reverse the process to install the new O2 sensor.
You cannot repair an O2 sensor. Replace it.
Ain't no fixing an O2 sensor. If there is a problem with it, replace it with a new one.
i got one for 80 bucks at napa
Around 90-100 dollars
With an o2 sensor socket.