How to Replace Downstream O2 Sensor 2007-17 Ford Expedition

All right, friends, it's gonna be time to get started on our downstream O2 sensor. First, you want to make sure that you have the correct O2 sensor. The downstream is gonna be the one that's located on the rearward aspect of the catalytic converter, and it's gonna have the shorter wire. The upstream O2 sensor is gonna be located on the same pipe, but it's gonna have a much longer wire and a different connector. I'm just going to use our O2 sensor socket here, we'll get it on there and break this free.

The next thing we would wanna do is follow that wire to the connector. There's gonna be a little push tab that you're going to push on, and then you're going to separate the two pieces. There we are. Go ahead and grab that wiring, bring it down to the O2 sensor and then remove your O2 sensor. There it is, friends. Now it's gonna be time to install our brand new O2 sensor. I'm just gonna take the wire go over the driveshaft. We'll go ahead and start this in, bottom it out and then we'll torque it to 46 foo-pounds. Just use a tiny bit of dielectric grease inside the electrical connector, and let's get it connected in, give it a nice click and a nice tug, make sure it's completely secured. And, of course, if it came off the bracket, just make sure you re-secure it with something. Lastly, let's go ahead and put this back inside there, and you should be good to go.