Oxygen Sensors

I do alot of my own work, but I was just wondering how hard it is to change the O2 sensors on a 200 Bravada? I was told not to worry about it if my mileage soesn't suffer, but I'm tired of looking at the light on the dash.

Hi Manny,
Do you know which code is stored? You might go to a chain type auto parts store for a free computer scan if you don't...we can discuss it here.

O2 sensors are more reliable than the error codes associated with them, and not cheap to just swap out without proper diagnosis. The O2 sensor is the last in the emission loop and as such is subject to being tripped by something up stream as simple as bad spark plug wires. When was the last major tune up done, and what parts were replaced? Usually O2 errors will not turn on the SES lamp until the next error and will go on and off during normal driving. Does yours stay on all the time?

I went to advance auto parts and they told me the code was for an o2 sensor. My SES light is on all the time

There are 36 or more trouble codes for O2 sensors and they're not all "bad O2 Sensor" codes, some are related to bad electrical grounding, poor connections or even fuel injection issues in which a new O2 sensor won't fix.
Do you know what number code came up on the code reader?