Catalytic converter

[Vizzo]

I think my cats are getting clogged or are just no longer working correctly because they keep tripping the check engine light. I have almost 150,000 miles so I'm sure they aren't working like they should. My question is should I get a high flow cat or take my cats off and have straight pipe? What about my O2 sensor if I take them off? If I put on a high flow cat, do I put it in place of the front or rear cat? Thanks for any help you can give.

[LargeFish]

You only have one cat. What I would suggest if you don't mind the car being a little louder, replace the cat and remove the resonator behind it and replace it with pipe. If you want to keep the car quiet, you can leave the resonator on if it's still good. Sometimes the resonator will get plugged up with pieces of the cat that break apart so check it out carefully if you don't remove it.

[Wallflower]

He can't simply remove the cat and forget about it because he has an OBD-II car. Removing the cat and not taking into account the downstream O2 sensor will result in a CEL. The best thing to do is replace the cat with an OEM unit from a company like Walker, or go with a high-flow from Magnaflow.

[LargeFish]

Who said anything about removing the cat? I mentioned he could optionally remove the resonator that is behind the cat. Walker cats are good, but I think Catco is the best value. I have a Walker on my GAGT, but if I had been better researched when I needed one, I would have went with a Catco from Summit.

[matts]

i say just rip it all down and start over fresh. headers, 3" pipe, no resonator or cat, and a muffler of your choice.......just kidding. is the resonator in a different spot on the 99 and up? when i had my girlfriends on the rack it looked like the resonator was not to far behind the manifold in front of the cat. i dont guess it really matters, because she already has a muffler that is plenty loud and she dont need it any louder, and im not paying for any more exhaust work. i already have $15 dollars invested in her exhaust system and thats enough:D

[LargeFish]

I'm not very familiar with the 99+ exhaust, but AFAIK the cat. always has to come first...

[digital-d]

I would not remove the cat cause I am sure where you are you have to pass an inspection, plus I don't think you would want to lose all your low end power. Catco seems to be a good brand for a hi-flow cat and they are only about $60 so your not going to throw a whole pay check into it. If you want to, you can remove your resinator, but the only thing that would do is make your exhaust slightly louder.

[Vizzo]

Michigan doesn't have inspections, but I just don't want to be tripping codes and having the CEL on all the time. I think I'll go with the Catco cat and remove the resonator. I don't care about sound as long as it doesn't hurt my car. It has 145,000 miles and has yet to burn a drop of oil. KNOCK ON WOOD...