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robselina
05-09-2005, 11:24 PM
I need to replace my cat and my mufler and I'm thinking I'll just stright pipe it from just before the cat into a new mufler with a 45degree tip. In other words, no more cat and no more funky exhaust routing above the axle.

Emissions legality isn't a concern where I live, and I only have a single O2 sensor before the cat.

I'm assuming the computer shouldn't give a crap since I don't have a post catalytic converter 02 sensor, but throught I'd ask the stupid question "just in case"......

Jeepinparrothead
05-09-2005, 11:28 PM
That is how mine is run. Works just fine. I tell everyone that asks me if there was ANY problems that I think that it messed up the EGR but I don't know for a fact. It ate a few quickly and I stopped putting new ones in. It throws a code every now and then.

Jim311
05-09-2005, 11:40 PM
Mine actually has the pre-cat and post cat sensors, and it throws no codes whatsoever, despite the cat being completely replaced with a piece of straight pipe. Go figure :D

Michael
05-10-2005, 12:20 AM
i was wandering the same thing. what engine do you guys have?

TrojanMan
05-10-2005, 12:36 AM
you'll be fine. If you do remove the cat and have a post-cat sensor you can build a sensor simulator sensor for under 5 bucks.

Jeepinparrothead
05-10-2005, 09:34 AM
5.2

Swamp boy
05-10-2005, 09:40 AM
I just pulled the post cat O2 sensor off and wrapped it around some crap and zipp tied it out of the way.. I have straight pipe off the manifold that runs to the Flowmaster then straight out.. NO O2 sensors at all..

robselina
05-10-2005, 07:06 PM
Cool, thanks for the confirmation on this. With how finiky the electrical system is on this thing I didn't want to get a nasty surprise...

Michael
05-10-2005, 09:22 PM
okay so my cat sounds like there is marbles in it when you kick it, or run it down a dirt road, so i'm guessing its shot. with a 4.0 can i just cut it off then take it to a muffler shop to get pipe installed? got quote for $40 for the pipe to be put back in, which seams high, but i don't care considering it will stop rattling. so what do i need to do with the sensors? or do i just cut it out and find out later? anyone think these cat peices have fucked up my muffler aswell? thanks :partyman:

nate
05-10-2005, 10:07 PM
Most muffler shops won't do that because it's illegal. Federal crime actually.

TrojanMan
05-10-2005, 11:28 PM
You'll be very, very hard pressed to find a shop that will do it.

Carl are you saying you don't run a pre-cat O2 sensor?

Swamp boy
05-10-2005, 11:36 PM
Pre cat O2 Sensor is welded into the pipe ( Fitting is at least..) but the down stream is just zip tied to the "frame"...


Oh and I didnt have any trouble finding a muffler shop to replace the cat with a piece of pipe.. He told me that I had to cut the cat out my self and bring it back to him and then he welded the pipe in... (He would not give me a reciept ... But who gives a shit...)

Talk to some of the Discount muffler places and you will find one that will do it.. like I said.. Make sure they know you are going to cut it out yourself and bring it to them to patch...

Carl

TrojanMan
05-10-2005, 11:45 PM
Good.. I thought you meant you didn't have one, I was about to have to slap you with an e-stick :weedman:

Some shops are real picky. I guess you will find the el-cheapo places that'll let you do that. One shop I went to wouldn't even put in my high flow cat to replace the straight pipe I had in there.

Jeepinparrothead
05-11-2005, 08:15 AM
There was one place here in Huntsville that would do it....it is now shut down :weedman: But essentially what he said was, "this jeep?" Yeah, "Ok, $50, I don't know you and I have never seen that POS unibody jeep before". he then pulled it in the garage and shut the door and cut it off. But yes it is a federal crime, $10000 fine for shops. Which is not much.

TrojanMan
05-11-2005, 04:20 PM
There was one place here in Huntsville that would do it....it is now shut down :weedman: But essentially what he said was, "this jeep?" Yeah, "Ok, $50, I don't know you and I have never seen that POS unibody jeep before". he then pulled it in the garage and shut the door and cut it off. But yes it is a federal crime, $10000 fine for shops. Which is not much.

I thought it was 50K? I guess not. There's also a fine for the owner of the vehicle isn't there?

Jeepinparrothead
05-11-2005, 04:29 PM
If you get caught, which around here all the cops have truck/jeeps with striaght pipes, then it is like 1000. The guy at the shop said it was a 10000 fine, but that is the only way I know so you may be right.

Jim311
05-11-2005, 05:36 PM
I just took mine to an exhaust shop out in the boonies. Told them the cat was clogged, and that I the problem taken care of, and I wanted a muffler that sounded better installed. 70 bucks later I was out on the highway cruisin :supz:

robselina
05-15-2005, 06:10 PM
got it taken care of today (local shop would have done it and has done it for me before, but I decided to take care of it myself). Also swapped out the high pressure line on the power steering system 'cause it was bleeding all over the place.

Anyway, that cat was clogged all to hell 'cause it flows a lot easier now. Little more power for sure, we'll find out about gas mileage soon enough...