Blown out Cat or what?

[Blackened300a]

Heres a video of the rattle I have after a cold start. It seems to go away after driving for a little while. Tonight I went for a drive out to Long Island and it seems to rattle all the time now. Blown out Stainless works cat or something else?
The exhaust is pretty tight, I haven't noticed anything moving or banging underneath and the exhaust seems to drone a bit more then usual and a lot louder under throttle.

o2o6nVO7D4Y

[DOOM]

How long has the exhaust system been on the car?

Isn't it fairly new?

[Blackened300a]

How long has the exhaust system been on the car?

Isn't it fairly new?

I believe it was July I picked it up. I maybe have 500 miles on the setup if that.

[DOOM]

:eek:
I believe it was July I picked it up. I maybe have 500 miles on the setup if that.

Doubt it would be the cats at only 500 miles! :eek:

But if it is the cats I would just gut them!

[Blackened300a]

:eek:

Doubt it would be the cats at only 500 miles! :eek:

But if it is the cats I would just gut them!

Why not? There are a few guys that have blown these out as well within a short amount of time. If its not the cats then what else could it be?

[justbob]

Sounds like something just came loose is all.

[DOOM]

Why not? There are a few guys that have blown these out as well within a short amount of time. If its not the cats then what else could it be?

Gut em out!!!

Rattle will be gone for sure! :up:


Thats what I would do if mine started to rattle! A few other members here have done the same.

[Krytin]

"Tonight I went for a drive out to Long Island and it seems to rattle all the time now."

It had nothing to do w/the drive home.:rolleyes:


That was the first time I broke the wheels loose leaving the parking lot - not even 200 miles on the rear.:D

The car sounds very nice and looks very strong when it's driving away!
Time to delete the cats!!!
It would be nice to get a credit on the failed unit(s).

[DOOM]

Sounds like something just came loose is all.

That's what I was thinking. 500 miles and cats are shot already!

It's not like you beat on the car.

Check everything thoroughly and make sure everything is nice & tight!

Do you have any type of warranty? It's only been 500 miles and barely 6 months.

[Blackened300a]

That's what I was thinking. 500 miles and cats are shot already!

It's not like you beat on the car.

Check everything thoroughly and make sure everything is nice & tight!

Do you have any type of warranty? It's only been 500 miles and barely 6 months.

Yeah SW said to take pics when I pull them off. I checked all my clamps and hangers, nothing is loose. Its possible they unraveled inside the cat and expand when they heat up which would be why I only hear it on cold starts and after the exhaust has cooled down.

Don't worry Paul, right after Lou put my rear together I did a hole shot as soon as I pulled out the garage. ;)
Like you said, the manual said nothing about a break in period, that goes for the transmission and rear as well.

[99SVT]

I've had the stock cats go and it sounded close to that, basically an annoying rattle in the exhaust. I've also seen near new cats from Kooks and SW come apart before, Mainly on GT500's, some shifted in the seat, others melted, and one split the casing.

Replace the cat or delete them altogether, your choice.

[Blackened300a]

Replace the cat or delete them altogether, your choice.

NYS inspection would strongly suggest I replace them. Also the exhaust is quite loud as it is, I would not wanna make it any louder in the least.

[Krytin]

Not worried about Lou's work - my car breaks traction alot easier now that all those cooked bearings are replaced!

Get some cat-delete pipes for your car. It will sound even better and might even net some more power! As long as you kept the pipes at 2 1/2" max ID you won't have any problem w/no cats.

And it's never too loud!!

[Blackened300a]

Not worried about Lou's work - my car breaks traction alot easier now that all those cooked bearings are replaced!

Get some cat-delete pipes for your car. It will sound even better and might even net some more power! As long as you kept the pipes at 2 1/2" max ID you won't have any problem w/no cats.

And it's never too loud!!

My exhaust is completely altered from stock. I have the headers that go into a collector that the cats clamp onto, then from there is a lead pipe that the cats clamp to that has a flange that bolts onto the stock H pipe. The option would be to gut them since I was able to see through them anyways, I just don't want that hallow raspy noise that will come with it. If I find the cats are destroyed then I'll see what SW will do for me as far as a replacement. Otherwise I'll go with a different brand metallic core set of cats.

[MOTOWN]

I would be very interested to see what the cats look like? sounds like it could very well be the catalyst having broke loose from the housings, especialy when you hit the gas at a stand still.

[Blackened300a]

Update:
Yesterday I spent a few hours under the car and pulled my exhaust apart. The drivers side Cat was intact and still solid. The passenger side cat I was able to move the element slightly back and forth and it seems the element cone is slightly starting to come out, but its nothing that would rattle. Eventually I would have to replace it if it continues to move. I also found a flange leak which I fixed and tightened everything as tight as possible. I pull the car off the lift and its still rattling away like it did before.
This morning I take the car to my friends shop so he can listen under the car while I throttle it. Turns out the internals of my passenger side muffler came apart and are rattling inside the muffler. You can hear it tapping around inside the muffler with a stethoscope at idle and then bouncing all over the place under throttle.
Looks like new mufflers and a new X or H pipe for spring time 2012.

[Krytin]

At least it's NOT a drive train or motor related problem!!