What is the 2004 Chevy Impala o2 sensor location?

The O2 sensor on a 2004 Chevy Impala is located after the catalytic converter, inside the exhauSTStream of the car. The sensor is about the size of a spark plug and protrudes into the engine exhauSTStream and senses the level of oxygen. The primary function of this sensor is to determine the level of oxygen in the exhaust. With these sensors, the engine makes the required adjustments for the smooth burning of gas and achieves maximum efficiency. A common reason for the check engine light to come on is a faulty o2 sensor. So do remember to get them inspected as one possible cause, in the event of a check engine light.