Removing catalytic converter on 94

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May 31, 2010
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I have a94 and dont need to do emission. The oem exhaust is still going strong and I like the way the oem fits and mounts. But my cats hit ocasionaly hit the sliders and at 340,000 are probably pretty cooked inside. Today I started noticing a slight burnt smell from that area. I had her on a trail so it might just be dirt, mud and grass on them. But what would be the downside to having a good shop replace the cat with a straight pipe? I would like a pip made with the oem flange mounts made so I can keep everything else oem. Would this effect anything on how the truck runs on a OBD1 truck?

Before I did the HG a 100,000 miles ago it was burning oil. So I figure the cats might be slightly clogged from that anyway. Truck runs great, no codes right now. Just something I have pondered about.
 
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Ever been stuck in line at a drive-through behind someone who's chopped their cats? I have. It's gross. That's the kind of modification I expect from those filthy Jeep "people".
I cant say I have. What is it that you notice? I grew up driving cars old enough that didnt have cats and cant say I ever new a difference.
 

Ozark80

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Apart from the smell, it'll sound like a vintage boat. I'd take it to a local muffler shop and see what they can do for you, maybe with a magnaflow cat or something like that.

You could try selling the OG cats to make up some of the cost.
 
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Thanks guys. That is what I wanted to know. I will probably see if the smell goes away and just leave it alone. It rattles some but before this slight smell never really gave me any problems.
 
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Thanks guys. That is what I wanted to know. I will probably see if the smell goes away and just leave it alone. It rattles some but before this slight smell never really gave me any problems.
If you choose to straight pipe it, you will need to install the diode in the O2 wires to fool the computer into thinking all is well.

There are a few threads about this. From what I understand, the 93's came with it, but the 94's need it and it's a different one for the 95+.

Without this, your truck will remain in open loop all the time and it will over fuel and drop your gas mileage. That may or may not be significant.

Basically it will think it's running cold all the time and hold the injectors open longer.
 
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If you choose to straight pipe it, you will need to install the diode in the O2 wires to fool the computer into thinking all is well.

There are a few threads about this. From what I understand, the 93's came with it, but the 94's need it and it's a different one for the 95+.

Without this, your truck will remain in open loop all the time and it will over fuel and drop your gas mileage. That may or may not be significant.

Basically it will think it's running cold all the time and hold the injectors open longer.
I run my O2 sensors in the PAIR manifold spots, before the converters obviously and haven't had any issues. I also ditched my cats and went with the Magnaflow y-pipe. Mine is a 94.
 

slow95z

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If you choose to straight pipe it, you will need to install the diode in the O2 wires to fool the computer into thinking all is well.

There are a few threads about this. From what I understand, the 93's came with it, but the 94's need it and it's a different one for the 95+.

Without this, your truck will remain in open loop all the time and it will over fuel and drop your gas mileage. That may or may not be significant.

Basically it will think it's running cold all the time and hold the injectors open longer.
Thats for the EGR, not cats.
 
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I cut both my cats out along time ago on my 94, sounds like one of those rice guys that try’s to race people, I have magna flow muffler. At high rpm’s the truck sounds dumb and it stinks, my wife and people would complain behind me some. I wouldn’t do it again I would do as suggested and run one cat and put it flat.
 
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I am having issues with high HC/CO and I used denatured alcohol for a quick fix and to pass emissions. But I do plan on having the cats replaced with either 2 universal weld in ones or one high flow cat from a reputable company and maybe at the same time have them redo the exhaust by replacing one muffler and eliminating the second one in the rear near the bumper.
 

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