Where is the oxygen sensor on 2006 Mazda 3?

On a 2006 Mazda 3, the oxygen sensor is typically located in two main positions: one upstream (pre-catalytic converter) in the exhaust manifold or exhaust pipe, and another downstream (post-catalytic converter) further along the exhaust system. To access these sensors, you may need to raise the vehicle and potentially remove some underbody shields. It's advisable to consult the vehicle's service manual for precise locations and instructions for your specific model.