The other day I ran over a manhole cover, my car is lowered and has LT headers with cats. I did it low speed, but put a good dent and basically flattened the round cat out a bit. It was fine on the ride home (50 miles) and got in it today drove about 30 miles and the racket started. If you rev or accelerate the engine, it makes a rattling noise. You can still hear it at idle as well. Best I can tell, it is that cat. I tapped on it and the other and you can hear it on that damaged cat. Am I correct?

 

If you found the cat damaged I'd say that's a pretty sure bet of what the problem is. I would get it replaced asap. Depending on the damage you don't want to risk the cat restricting flow a lot. Could cause some major problems to your engine. Better yet get an offroad h-pipe or x-pipe. Then you don't have to worry about the cats at all and it will make your car sound better!

I'd also check that the clamps are tight on your exhaust. At the least it couldn't hurt and then you won't have to worry about an exhaust leak incase anything came loose.

 

Ya ditch the cats and get a h-pype. Sounds like u busted up the internals. Sucks, but so do cats.

 

Our state has a OBD II test, so the cats have to stay.

 

Dohh, then buy hi flow setup since u have to atleast replace the one.

 

Man i love texas, the only thing they do for inspection is ask if you have a legal exhaust. If you say yes then they give you the sticker and your on your way.

 

If you really want to avoid inspection problems...join the military! Haha, basically exempt from inspections for anything as long as you don't live in the state in which your car is registered.

But yeah, sounds like you'll have to get a new cat.

 

yep busted the guts

 

Not sure where you are in Texas, but you had better have cats on when you get your car inspected in Fort Worth or Dallas and most of the surrounding cities.

 

Well i know most of the northern part of texas they are converting to sniffers and computer tests but down here near brownsville and McAllen the little garages that do the tests can not afford all the equipment so i can the sticker easily.

 

Busted cat sounds like rocks in a coffee can, not that I know from experiance or anything. With the long tubes he already has hi flow cats, so just replace them. They can be found for around $50 for ceramic and $100 for metallic. I'd bet your current ones are ceramic if they broke like that. Just have to decide on welding them in or using clamps. With clamps they can be swapped out to make it O/R pipes for those special occasions.

 

in my part of texas, they dont even do that. I drive up, he scans the tag in the door, and prints up a new tag.

 

Last year for my inspection they didn't check my exhaust. Basically just checked if the horn worked, turn signals and that was about it.

So hi-flow cats or oem? I'd say if you're going to make the expenditure, pick up a catted X or something.

 

I called SLP and got a replacement and will install it tomorrow. It is just clamped on. BTW I emailed LM Performace first for help, no reply, no sorry we cant help, no, nothing at all. Kind of crappy customer service.

Unrelated question, can we do exhaust cut outs after the cats? or will that mess up the computer and the back pressure issue??

 

My state also has OBD II tests (Maryland), and I just passed emissions testing without cats...