Problems with my KJ

[jeepkj02]

So I got a P0442 code few months ago, so I tightened the gas cap and pulled the neg. battery terminal. Came back and decided to buy a gas cap. Long story short, I ended up replacing the spark plugs and negative battery terminal (cracked and corroded). When I pulled the last plug (pass. side, near coolant tank) I found it was covered in fuel. Meaning that cylinder is running rich. What could be causing this? Light is still on, I also noticed my muffler is leaking, so I need a new one.

Here is my list so far:
Flowmaster Super 44
Flowmaster Super 40
Flowmaster Super 50
Cherry Bomb Pro

Also I have another question, all KJ 2003+ don't have a cat before the muffler, when I install the new muffler would it be okay to cut it off. I'm thinking it might be clogged?

 

[t_bois]

Federal law says NO on cutting the CAT off (that's between you and Feds) plus if you have an emissions program in your state, you will not pass without a CAT.

There is a long warrenty on most CATs, so call a couple of dealers for warrenty information if you think the CAT is bad.

Run the motor for 1/2 hour on the hi-way or around town and then re-check the sparkplug. Could be the old spark plug was the problem; could also be a plug wire, ignition problem, injector problem, or worse case a compression problem.

Flowmaster is way better then a Cherry Bomb. I'm not sure I'd go with the least restrictive one as they are very efficent. More noise does not mean more performance on a stock motor.

Got a service manual? If not, I'd get a good factory manual from EBay or... If you find a deal on one for an 06, let me know. Infact, you may want to do a post as there may be others that want one.

 

[Atrus]

^^ What he said.

Also, it's very possible the cat is bad given the problem of the rich cylinder.