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missing cat

xjwisconsin

NAXJA Forum User
98, 4.0, ax15, np231,

PO removed the cat and cut the wires at the plug. Getting intermittent bucking and drag ass acceleration at times, usually in wet weather. Can I have a bung welded into the straight or do I need to cut it and replace the cat? no codes thrown, just running really rich.
 
im not not one to run catless, and I admit I am a moron for not noticing that it was missing when I purchased. Just looking for a short term fix (never ends well). Until I can muster up the money to get it working correctly.
 
Since it is ALREADY REMOVED.. I will say that the downstream O2 only monitors cat efficincy. O2 sensor before cat is what monitors the important stuff. Is that not connected? A CEL would be on I imagine if it was not.
So, the correct answer is, yes, replace the cat. But it sounds like you have a different issue.
 
Maybe--

U-Pull-It JY: - rubber mallot- find a cat that fits and don't rattle. Grab a pair of O2's and wiring. And a TPS or whole throttle body. (suspect TPS is part of goofy running)

Good Luck
 
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Don't know about your JYs, but cats are the first thing that get torched and removed, along with the batteries, the gas tanks, and the coolant before it hits the yard.
 
Have you tried putting up posters with pictures in your neighborhood? Sadly it's likely a coyote got it...

oh that kind of cat?

Don't know about your JYs, but cats are the first thing that get torched and removed, along with the batteries, the gas tanks, and the coolant before it hits the yard.
They pull wheels, batteries, cats, and gas at my yard. I got a couple gallons of gas with my first gas tank I bought, second tank they gave me for the cost of a pump only because they had drilled a 1/2" hole through the bottom of it to drain the gas. I know they don't drain oil, coolant, diff fluid, tranny fluid, AC refrigerant, or brake fluid at my yard :twak: because I have had all of those pour out on me or spray me when I opened the respective lines.

The Nashville Pull a Part slashes each gas tank open.
That just sucks...
 
Especially when you are looking for an MJ sending unit and you want the whole tank to be plug and play.
:smsoap: seriously

I have been looking for a whole sending unit (not even the tank included) brand new for a week now (for my 91 SWB 4.0), haven't found anyone selling one. Everyone thinks a 91-93 XJ one will fit though! :dunce:

As for the cat - if you need wire colors for the O2 sensor I can probably look them up pretty easily, then you can install it. I would really put a cat back in there ASAP though.
 
mine is so badly rusted I'm not going to be able to reuse it :( even though my pump works great.

Might have to fab something... ugh. I should just go with a fuel cell.
 
Yeah... probably a good plan. Dynomax is doing a mail in rebate right now, I think it brings a cat-back down to $75 at the moment? Not too sure. I was looking at getting one for my XJ on summit racing last week and decided it can bounce/rattle for a bit longer.
 
your issue is definitely not related to the cat/rear O2, the cat on my 97 went tits up and the new CA laws are retarded so I have been running no cat and no rear O2 with no problems. CA won't let you buy a cat unless you are a certified shop, and they want $700 for just the cat, so I have to make a trip to arizona to buy a new F'N cat
 
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