Where are the o2 sensors on a 2000 Ford Contour?

On a 2000 Ford Contour, there are typically two oxygen sensors: one upstream (pre-catalytic converter) and one downstream (post-catalytic converter). The upstream sensor is located on the exhaust manifold or just after the manifold, while the downstream sensor is positioned after the catalytic converter along the exhaust pipe. Both sensors can be accessed from underneath the vehicle, although you may need to raise the car for better access.