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Possibly a bad cat?

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Old Jul 26, 2006 | 10:55 PM
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Default Possibly a bad cat?

As of recently I have noticed my car doesnt perform as well as it should be as well as getting somewhat quieter. Another thing that Ive noticed is a rattle (kind of like a loose bolt in a pipe sound) from under the car at idle and lower speeds.

Could this be a clogged cat?
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Old Jul 26, 2006 | 11:11 PM
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Do you have any check engine lights on? Also what do you mean "doesnt perform" is their a loss of power or is it just hesitating when you take off
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Old Jul 26, 2006 | 11:38 PM
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No check engine lights. I dont have the rear 02s hooked up. Sorry let me elaborate a little on my setup.

I have Pacesetter LTs with a custom y-pipe and 1 hi flow cat after the Y. Dont ask me why I did this. I realize it is pointless to have the cat so far back.


Its kinda like this

Headers--------
......................---y pipe----------hi flow cat---------loudmouth
Headers--------

As far as performance goes I have noticed a very slight drop in power. Not a great loss but its definately noticeable. And like I mentioned the exhaust seems to not be as loud.
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Old Jul 28, 2006 | 12:27 AM
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**UPDATE**


So it turns out to be a clogged cat. On my way down to the shop I had to get on the highway. While I was on the onramp I hit about 4k RPMs and heard a *pop* and a bunch of **** fly out the back of the tailpipes. Since then it has been LOUD as *****. A-FRICKING-LOT louder than when the cat was first installed.

Anyhow its getting gutted as we speak. Thought Id update.
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Old Jul 28, 2006 | 02:24 AM
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Originally Posted by Shamson5.7
**UPDATE**


So it turns out to be a clogged cat. On my way down to the shop I had to get on the highway. While I was on the onramp I hit about 4k RPMs and heard a *pop* and a bunch of **** fly out the back of the tailpipes. Since then it has been LOUD as *****. A-FRICKING-LOT louder than when the cat was first installed.

Anyhow its getting gutted as we speak. Thought Id update.
That must have been funny. Sounds like you blew everything out of the cat already. When my passenger side cat when bad, it was making a horrible rattling sound, and if I gave it more than half throttle, the car just fell on its face. Luckily smog parts are warrantied for a while, so the dealer replaced it for free. It didn't set the check engine light on, which I thought was kind of weird.
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Old Jul 29, 2006 | 10:53 PM
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Yeah thats actually the same problem im having with my car, every time i give it throttle i hear this annoying rattling sound coming from the bottom the car. At this point i dont know whether i should just remove to get rid of the noise because im planning on changing the whole exhaust system.
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