I have to replace the piece of pipe right before the cat and it has the what i believe is the O2 sensor. (correct me if im wrong please) Does it just pull out or do i need to take it off a certain way and im assuming that it will go on the new pipe the opposite way. The bolts rusted off so i need to switch out that piece of pipe. Thanx in advance for the help.

 

yes it is an o2 sensor and they just unscrew.

 

yeah all you need is the slotted socket so the cable doesn't get tangled and it should come out no problem

 

I had to replace that same small pipe on my 02 Protege. I took a box end wrench and cut a small slot in it with a zip cutter to get it around the O2 sensor wire. Before you bother doing this, don't. The sensor was seized on there so bad that the box end just started "opening" where I had cut the slot. The solution, believe it or not: Spray the crap out of it with a good quality penetrating oil then use a medium sized pipe wrench. (10" or 12") Take your time and go slow. It is threaded on and will come off. Worked for me.

 

Oxygen Sensor replacement could be very difficult.

 

Rear Oxygen sensor Replacement . Soaked with WD 40 cloth overnite around sensor .
Oxygen sensor socket very tricky - won't stay straight -went by angle and Sensor pin broke . Good - much easy to work without it . On the cold engine I was unable to remove sensor . Wrench handle to short. I went to the store to get regular 7/8" wrench with foot long handle. Click- and sensor came out .