Tomorrow, I will get my car back from the exhaust shop where they're removing one cat from my 03 G35 sedan. I wanted to know if I should remove the O2 sensor as well.

I may have read somewhere that the O2 sensor could cause decreased performance, or something along those lines, I don't know for sure, this is the first car I've modded.

Any info will help.

 

i would hope that what ever pipe they replace your cat with it has an 02 bung.
and not to mention i would hope they take out both cats. cause otherwise you will have uneven exhaust flow and prob decreased performance from it.

 

What is an O2 bung and why would it need one?

 

You might want to read up on this info before you take your car from the shop...

An O2 bung in the most simplistic terms is basically a nut welded to the exhaust with a hole drilled in the pipe and the O2 sensor threads into the nut.

These cars have TWO cats, not one.

 

I'll let them know to remove both, if they haven't already figured it out.

So I need to have the O2 sensors installed?