How do you change out the oxygen sensors on a 2004 ford expedition?

Answer 1

I just replaced two O2 sensors on my 2004 Ford Expedition 4.6L. Basically, I took the car into Advance Auto and they plugged in their diagnostic tool and told me to replace the two that are between the engine and the CAT, they also lent me the sockets needed to perform the job. These sockets are a must!! There is no way I could have changed the passenger side O2 sensor without them. Okay to start the driver's side is very easy to find, its in between the engine and the CAT. First unhook the wire and then unscrew the O2 sensor....screw the new one in (other posts say to apply anti seize but it is already on the O2 sensor) then plug the wire back in. Now....the passenger side was a bear. The only way that I could find to get to it was to undo the rear most plastic well set pin (it goes right back in) and from beneath the car push the plastic wheel well toward the tire and access the o2 sensor from above the frame. A person with smaller hands will have an easier time doing this...but for me this one took a good 30 min. The hardest part was getting the new O2 sensor threaded into the hole as I was unable to see anything that I was doing and had to work by feel. Regardless, this is definitely a do it yourself job, you just have to be very patient, and maybe if you are lucky you can knock it out faster than I did. Oh....one final note...I worked on the car a good two hours after driving it and things were still somewhat hot under there. You will not be able to wear gloves to do this as it is just too tight under there so definitely wait until everything has cooled down.