Change O2 Sensor

[TimothyKell]

I have a 1998 SE, 4-cyl 2.0 automatic tx, and I would like to change the O2 sensors in my car. However, I can only locate 1 of the sensors - as I lay underneath the car, it is toward the front of car near the passenger wheel. As I understand it, there are 2 sensors on this car. Where specifically would the 2nd sensor be - in the engine compartment, near the rear of the car, etc?

 

[striker2]

the one you can see from under the car is the lower or downstream sensor (sensor 2). the upstream sensor (sensor 1) is located in the exhaust manifold before the catalytic converter, looking from above the engine bay. removing the exhaust manifold heat shield will make it easier to see and get to, but i dont believe its necessary on the 98+ Zetec.

 

[TimothyKell]

striker2, thanks for that. What side of the engine bay would that be on, or whereabout in the engine bay would that be?

 

[FIND]

both O2 sensors are mounted on your exhaust. The upstream sensor is on your exhaust manifold which comes out of the front of your engine. You should be able to see the sensor if you look down inside your engine bay from the top. Just follow your manifold down.

 

[striker2]

look down between the radiator and the valve cover and you should be able to see it.