In any engine it usually means your piston rings are worn.
The PCV system is not working properly or the engine has excessive blow-by (engine is tired).
You will have to unbolt and remove the engine access cover inside the passenger compartment. Then you can easily get to the air cleaner.
The 2002 Chevy Cavalier 02 sensor can be found attached to the air cleaner housing. The O2 sensor will be on the back side of the air cleaner housing.
Top of engine under air cleaner
The Chevy air cleaner is a vital component for the efficient running of your vehicle. It filters out any dirt and grime out of the air before it passes into the engine, this in turn allows the engine to operate at peak performance and fuel efficiency.
Take the air cleaner off and you will see the carburetor bolted to the top center of the engine. That is what the air cleaner set's on. The top of the carb.
Under the air cleaner box
on top of the engine, under the air cleaner
the emissions pump and system pull some of the exhaust out of the pipes and send it back to the air cleaner (reusing the air in the exhaust) and i guess that way it polutes less
In front of the air cleaner, on the air induction system.
It doesn't have one.
On the tube between the air cleaner and the throttle body
it is on the valve cover. tubed over to the air cleaner