Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

Possibly a bad cat?

Thread Tools
 
Search this Thread
 
Old Jul 26, 2006 | 10:55 PM
  #1  
Shamson5.7's Avatar
Thread Starter
TECH Enthusiast
iTrader: (5)
 
Joined: Oct 2005
Posts: 676
Likes: 0
From: Denver
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?
Reply
Old Jul 26, 2006 | 11:11 PM
  #2  
Starz T/A 17's Avatar
TECH Addict
iTrader: (6)
 
Joined: Jul 2005
Posts: 2,855
Likes: 0
Default

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
Reply
Old Jul 26, 2006 | 11:38 PM
  #3  
Shamson5.7's Avatar
Thread Starter
TECH Enthusiast
iTrader: (5)
 
Joined: Oct 2005
Posts: 676
Likes: 0
From: Denver
Default

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.
Reply
Old Jul 28, 2006 | 12:27 AM
  #4  
Shamson5.7's Avatar
Thread Starter
TECH Enthusiast
iTrader: (5)
 
Joined: Oct 2005
Posts: 676
Likes: 0
From: Denver
Default

**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.
Reply
Old Jul 28, 2006 | 02:24 AM
  #5  
Jimmard's Avatar
TECH Resident
20 Year Member
iTrader: (12)
 
Joined: Sep 2004
Posts: 782
Likes: 0
From: Newhall, CA
Default

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.
Reply
Old Jul 29, 2006 | 10:53 PM
  #6  
Kings Fan's Avatar
Teching In
 
Joined: Jul 2006
Posts: 16
Likes: 0
From: California
Default

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.
Reply




All times are GMT -5. The time now is 10:13 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE