How many o2 sensors will be on the unit? I know the one that is visible on the top of the manifold... but are there any others?

I do have that gasket.

So I shouldn't have to remove the bumper or jack up the car should i?

 

lol, and any advice on removing the o2 sensor? I remember this being very difficult on my old civic. The mechanic I finally had take it off used some spray that helped alot. Any idea what that might be?

The instruction manual for the cat conv recommends putting a new o2 sensor in.. is that a good idea?

 

Best option to remove an O2 sensor is to use a special socket (it looks like a regular 6point deep socket, except there is a slot down one side for the wire that's attached to the sensor)

If you don't have one of those you can attempt my method. I'm 3 for 3 with it, but it doesn't mean it's the best.

Silver's Advice:
Locate the O2 sensor you want to remove, disconnect the wiring harness (or if someone has hard-wired it, cut it where it has been spliced)
Locate proper sized wrench, and a bottle of penetrating fluid (WD-40 or similar)
Spray down the exposed threads - really soak them
Locate cold beer can (unopened), pack of cigarettes, or similar.
Relax for aprox 10 minutes.
Respray threads
Relax for another 10 minutes
Place box end of wrench over sensor. Position wrench for best clearance
Firmly shove wrench. it SHOULD crack loose.
If not, Tap wrench with hammer.
At this point all O2 sensors give up and I'm able to thread it out.

I hope that the above guide helps!


There are 2 sensors, 1 above and 1 just below the cat. If your exhaust is completely cold, remove the top heat shield from the cat, and have a look at the O2 sensor. The same thing is screwed into the bottom pipe, very close to the bottom of the cat.

Good luck!

 

NO WD40.

Use PB Blaster. It's amazing.

 

Alright cool. Ordered some PB Blaster and a socket off of amazon. I will switch out the cat on Sunday when my dad can give me a hand.