Got a 2001 Monte Carlo SS, Check Engine light came on the other day, went to Auto Zone got it checked and this was the code:






P0133

HO2S/O2S Slow Response Sensor 1 Or Bank 1 Sensor 1


Few questions, Is this a real serious problem?

Easy Fix?

Where is it located? Easy to get at? Time Consuming?

The Oxygen Sensor costs $67.99, autozone said this would fix the problem, they also said it could hurt the Cat if I keep running without replacing it. Any advice? tips?

 

Oxygen sensor #1 is located in the rear exhaust manifold. I don't recommend trying to change it yourself unless you have an oxygen sensor socket. This code can also be caused by contaminated fuel or an exhaust leak,but the most common cause is the sensor itself. Not repairing this condition could eventually lead to catalytic converter damage. The following is the explanation directly from GM Service Information.....
The powertrain control module (PCM) continuously monitors the heated oxygen sensor (HO2S) activity for 100seconds. During the monitoring period, the PCM counts the number of times that a rich- to-lean and a lean-to-rich response is indicated. The PCM also adds the amount of time taken to complete all transitions. With this information, an average time for each transition can be determined. A lean-to-rich transition is indicated when the HO2S voltage changes from less than 300mV to more than 600mV. A rich-to-lean transition is indicated when the HO2S voltage changes from more than 600mV to less than 300mV. An HO2S that responds too slowly is likely to be malfunctioning and should be replaced. If the average response time is too slow, DTCP0133 will set.

 

You can do this yourself and save yourself a bundle. You will need some penetrating fluid, an oxygen sensor socket, a breaker bar and a ratchet. At the back of the 3.8, located on the rear exhaust manifold, you will see the sensor threaded into the manifold. It will have four wires in a bundle leading up to a black connector. Apply a heavy application of penetrating fluid to the threads of the sensor and let it sit for a hour. Disconnect the connector, slide the socket onto the sensor, guiding the wire into the channel cut into the socket. Using the breaker bar, apply firm, steady force to break the threads loose. Remove the old sensor. Apply anti seize on the threads of the new sensor, taking care not to contaminate the sensor tip in any way. Install the sensor and torque it the manufactures specs. Easy-peezy...

 

Just as a FYI, the thread is from 2008 and the OP hasn't been online in a decade.