Opinions on Catalytic Converters...mine is done for

[W00GYB00GY]

So when I first bought my jeep I could hear the dreaded rattle. It is extremely annoying and I really just want to cut it off, as well as the muffler and straight pipe it but I'm not sure if that's a good idea.

I have a 96 XJ so my o2 sensor is in the front of the cat, so if I took the cat out I'd have to relocate the o2 sensor I'm guessing, not sure how difficult that would be.

I tried taking off my cat earlier today but it was a pain in the a$$...I got both U bolts off and the cat is NOT welded on. I'm just assuming that since it hasn't been replaced since 1996 it doesn't want to come out. Depending on what you guys think about straight piping my jeep, I'll just cut it out and clamp on the straight pipe with a resonator tip at the end.

Let me know what you guys think!!!

[Mudderoy]

So when I first bought my jeep I could hear the dreaded rattle. It is extremely annoying and I really just want to cut it off, as well as the muffler and straight pipe it but I'm not sure if that's a good idea.

I have a 96 XJ so my o2 sensor is in the front of the cat, so if I took the cat out I'd have to relocate the o2 sensor I'm guessing, not sure how difficult that would be.

I tried taking off my cat earlier today but it was a pain in the a$$...I got both U bolts off and the cat is NOT welded on. I'm just assuming that since it hasn't been replaced since 1996 it doesn't want to come out. Depending on what you guys think about straight piping my jeep, I'll just cut it out and clamp on the straight pipe with a resonator tip at the end.

Let me know what you guys think!!!

I bought a $99 catalytic converter and a $100(?) off road muffler from Summit. I paid a muffler shop $100 to install them. He asked me how much I paid for the converter, I told him. He said that was a great price, he sells the same one for $250. lol

http://xjtalk.com/images/special/MyNextMuffler.jpg

http://xjtalk.com/images/special/JeepNewMufflerCat.jpg

[bigjim350]

Does your o2 sensor screw into the cat? If it does you can just get the cat off and gut it and put it back on. If its not, just leave the o2 where it is and put in a straight pipe. Do you have an o2 after the cat?

[cantab27]

easy fix...thats mine there...

http://i469.photobucket.com/albums/rr52/cantab27/jeepin%20and%20bits/Image0629.jpg

oh hang the pussy gone

[Joliet Johnny]

if you gut the cat you may want to jam a pipe through it as to not disrupt the flow of exhaust. Personally Id sell the cat to one of those places that harvests the expensive metals from them.

[bigjim350]

Oh yeah, and here is a pic of my "cat"
http://i20.photobucket.com/albums/b249/bigjim350/003-7.jpg

[Firemanray]

Threason it wont come off is the clamps have "hour glassed" the sleeve and pipe together. I had this same problem when i gutted mine. I ended up splitting the sleeve and spreading it out to release the pipe.

[Mudderoy]

Oh yeah, and here is a pic of my "cat"
http://i20.photobucket.com/albums/b249/bigjim350/003-7.jpg

lol i love this image.

[Mudderoy]

Although this would be closer to proper installation of that cat...

http://www.stevenhumour.com/wp-content/uploads/2011/04/cat-on-a-pipe.jpg

[W00GYB00GY]

I'm pretty sure I only have one o2 sensor and its screwed into the cat, I would like to just straight pipe it, remove the cat and muffler and be done. But not sure if its really a good idea.

[bigjim350]

Well you would need to weld in a bung for the o2 sesnor on the straight pipe. It probably will set off a check engine light, but if it does do this mod http://www.355nation.net/forum/how-performance-maintenance/401-how-install-o2-sensor-non-fouler-eliminate-check-engine-light-pics.html and that should fix it. In my opinion I dont see a reason not too. It MAY run a LITTLE rich, but shouldn't amount to any notciable mpg lose. Same say you lose hp and tq but mine will still smoke the 33's with 3.55 gears. Now if ya have to pass emission insp it could be difficult. And if ya dont some strict places might not pass a visual inspection if they dont see it under there. Thats where the gutted one is nice.

[msmoorenburg]

Cat's such a frisky subject

[W00GYB00GY]

Well...what a complete waste of a day. It started ok, but then it all fell apart...

I started working on my cat at 10:30, cut it out and ripped the muffler out by like 11:30 then I cleaned out the cat, took it down to Auto Zone, got the clamps and piping I needed, came home and tried it all out.

The cat wouldn't fit on the muffler because I cut to much of the cat off so there wasn't enough room to clamp, and then I finally got it clamped on there (or so I thought) and I had it under my jeep bolted it all together and realized my cat was upside down and flipped around.....I was furious!

So then I had to take it all down again and then one of the clamps had tightened down so much on my cat that I couldn't get it off so I tried using a hammer to get it off and then I accidently smashed my O2 sensor...this is what I said FU*K this...and pretty much gave up and I'm just going to straight pipe it...

So now I have no exhaust/muffler/cat, and to top it all off my O2 sensor is smashed...seriously the worst case scenario...

[cantab27]

no no no ..worst case scenario would be if ya jeep was red.....
thought 02 wouldn't be that much $$ over there....$140 here

[W00GYB00GY]

Well surprise, surprise, after driving it a total of 50 +- miles without the cat/o2 sensor on the cat my check engine light came on...

nowwhattodo...?

[bigjim350]

Either live with the check engine light, if its running fine. Or put in a new sensor.

[bluedragon436]

I would say either put in a new O2 sensor, or stop by a pick-n-pull and pick up a used one to tie you over for a bit.. Then reset your PCM, so you won't have the CEL anymore...

And Jim... didn't that pic get you in trouble the last time you posted it??

[bigjim350]

And Jim... didn't that pic get you in trouble the last time you posted it??

Not on THIS site....:rolleye0012:

[Jarlaxle]

deleted

[W00GYB00GY]

Well I just got back from the junkyard, and got 2 o2 sensors, I'm going to have my friend put a straight pipe on and put the o2 sensor in the straight pipe with a bung.

Hopefully it'll work...

[Jarlaxle]

...............

[bigjim350]

If you use the foulers on that's sensor it should work fine with no cel. His jeep is an early 96 produced in 95 so it's most likely obd1

Sent from my VM670

[Carves]

It won't. Anything 1996-newer has sensors before & after the cat. No cxat means a CEL.


96 on should be OBD2 ...

Going by my interpretation of the FSM ....

Upstream sensor fine tunes the preset fuel mixes, in conjunction with the various other sensors ...
Downstream sensor is to provide a CEL when the cat is unserviceable ... or missing.

Dont mind the idea of cat converters ... probably a good thing for commute vehicles doing short hops in suburbia ... but a damn nuisance for some vehicles in other operating scenarios.

Typically ... they are another govt blanket legislation that didnt take into consideration, everybodies needs.

[W00GYB00GY]

So putting a bung in the straight pipe and putting the o2 sensor in there wouldn't work?

[Mudderoy]

So putting a bung in the straight pipe and putting the o2 sensor in there wouldn't work?

I think I remember reading that the 2nd O2 sensor reads how well the catalytic converter is doing it's job. With a 2nd O2 sensor and NO catalytic converter I'm thinking the ECM will think the catalytic converter needs to be replaced.

[4.3LXJ]

Yes, you need a cat for the second sensor to function properly. Without a cat there, it will give you a CEL

[W00GYB00GY]

Sow do people straight pipe there jeeps and it not throw a CEL??? What are my options besides putting a cat in?

[4.3LXJ]

You can do it with the Renix era XJs. However to avoid a CEL on your OBDI Jeep you need a cat in between the O2 sensors. There also may be some issues with a need for back pressure to allow the ECM to make your engine run efficiently. It is the way the ECM is programed.

[Firemanray]

Well I see all the drama got deleted, including mine.

I would give the spark plug anti-fouler trick, a try. Big Jim told me about it, I need to do it to mine since I have a "gutless" cat and a CEL. I think he posted a link further back in the thread. Makes since to me that it could work, I just been to busy with other things to try it. Be sure to post up if you try it and it works.

[W00GYB00GY]

What about the fowlers method because I know there's a way you can avoid throwing a cel without a cat.

[W00GYB00GY]

Yeah I'll probably try the fowlers trick and see how that works...I don't see how it couldn't, but I'll post pics and stuff, i'll do it this weekend.

[bigjim350]

My obd1 jeep has no cat, and has NO "check engine" light on. I didnt even use the foulers on mine. Just yanked the cat and put in a straight pipe. And yes the light does work.

[msmoorenburg]

I've done the anti-fouler trick and it worked on my application. it kept the light off till the car was inspected. New Texas Laws to transfer title it must passed obd inspection if never inspected in that county. Long term i have no clue the car became a srt4 clone so all parts were used from a donor.

[LizardRunner]

when I got da lizard there was a nearly new looking cat under there. When it decided to start rattling, (I almost sure it had nothing to do with me smacking it all over with a 3lb dead blow hammer) I pulled it, took it apart, emptied it and put it back together. Now it looks like I have a cat but in reality it's more of a resonator chamber. When they checked the emissions for me, it was good to go for Arkansas.

[Mudderoy]

I remember when catalytic converters first came out. No one liked them. We felt that the federal government was again sticking their nose further up our butts. Around 1984 I had a 1982 Z28 that was loosing power. After asking around several people said it was probably the catalytic converter getting clogged from using leaded gas. (I think that's right). I hated the damn thing and they were $300 or more back then.

I took a log 3/4" steel pipe and made quick work of all that honey comb stuff. I think I was spewing honeycomb for the next two weeks out the back end.

Now days you can get a catalytic converter for $100 so it's less of a deal to me.

[Cranesrule]

There is a RECALL on 1996 XJ catalytic converters for the rattle and a PCM flash. I had mine done about a month ago with 183k miles and they also replaced the O2 sensor that they broke trying to get it out. Go to the owners area of the Jeep site and you can enter your vin to see if your rig is (was) eligible.

[Cranesrule]

Sorry I didn't see this earlier.....