Where are the oxygen sensors located on a 2000 Toyota Echo?

Answer 1

This answer will first describe the exhaust system of the 2000 Toyota Echo and then attempt to describe where the oxygen sensors are located.

The exhaust system of the 2000 Toyota Echo is a two piece unit. One piece is the muffler with a little piping at either end (located at the rear of the vehicle - the rearmost bit is open pipe from which exhaust exits the vehicle). The other part extends from the muffler all the way to the engine area of the vehicle.

Starting from the muffler and working forward with the exhaust system one sees two bits of the front pipe that are larger in size than the pipe itself. These bits are the resonator (located near the middle of the vehicle) and the catalytic converter, located toward the front of the vehicle (but still well behind the engine area.

The oxygen sensors are located in front of and behind the catalytic converter mounted into the exhaust pipe itself. The sensors have wires coming out of them - when looking at them for the first time, looking for something with wires attached sticking out of the exhaust pipe is a good way to find them.

If the author remembers correctly, the frontmost sensor (closest to the engine) comes out of the exhaust pipe toward the driver side while the rearmost sensor comes out toward the passenger side.

Sensor 1 is the sensor closest to the front of the car and the other sensor is sensor 2.