I am getting an odd sputter sporadically. By that I mean that I am having gas detonate in the manifold or down tube. I checked / replaced plugs, cap and rotor and still have the issue just less frequently. I'm planning to pull the cat off to see if that helps. I saw that it still has the origional muffler which can't be all that great. My real question is will I have issues with the O2 sensor? Any one know? Help.....

 

you have a pm

 

yes you will,the 02 sensor down stream of the cat is checking efficency of the cat and makes adjustsments to the front 02 sensor which adjusts injector pulse width or on time.,it will cause a rich condition without the second 02 sensor . also I am sur you plan on replacing the cat with a new one or the old one if it is good? reason being it is illeagal to run without it,and in your case it would not run well anyway.
Cats are not the only restrictions,your muffle you said is old,I would look at it closley also. Sometimes when the cat comes apart it will end up in the muffler.

 

https://www.cherokeeforum.com/f2/cat...er-laws-24337/

 

Closed, if it's not obvious why well read the tech area stickies.