Cat question

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Apr 20, 2013 | 03:17 PM

TKT-MKR

Thread Starter

Burning Brakes

Joined: Jan 2008

Posts: 1,120

Likes: 1

From: Biloxi Ms

Cat question

So while under my car today, I noticed that one of my aftermarket cats is discolored (brownish/bronzing color) while the other still looks silver (or similar to new).
I have aftermarket headers and a Corsa exhaust also.
Just think it is weird that one cat would be discolored like that. Almost like it is getting too hot (or something)

Any comments

Apr 20, 2013 | 09:28 PM

NukeC5

Melting Slicks

Joined: Jun 2012

Posts: 3,163

Likes: 6

From: Oceanside California

One bank is likely running leaner than the other, which is making that cat get hotter.

Apr 20, 2013 | 11:12 PM

TKT-MKR

Thread Starter

Burning Brakes

Joined: Jan 2008

Posts: 1,120

Likes: 1

From: Biloxi Ms

and why would that happen?
it isnt like I really have any codes

Apr 20, 2013 | 11:38 PM

GoatKart

Instructor

Joined: Mar 2006

Posts: 220

Likes: 0

From: ames ia

can happen if one of your cats gets slightly plugged or the honeycomb partly collapses... or maybe the injectors in that bank flow a little less fuel...

Numerous reasons it COULD happen...

Apr 20, 2013 | 11:54 PM

moosifer

Instructor

Joined: Oct 2009

Posts: 215

Likes: 1

From: Roseville CA

Check the condition of the plugs on that bank. If they look ok, then that bank is not running lean and you can rule fuel and spark out of the equation.

Apr 21, 2013 | 12:19 AM

Bill Curlee

Tech Contributor

Joined: Dec 1999

Posts: 32,910

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From: Anthony TX

CI 6,7,8,9,11 Vet

St. Jude Donor '08

Check the CAT Temp with a digital laser thermometer and see if the CAT/s are both coming up to temp. If one is COLD, its likely damaged.

Bill

Apr 21, 2013 | 06:13 AM

TKT-MKR

Thread Starter

Burning Brakes

Joined: Jan 2008

Posts: 1,120

Likes: 1

From: Biloxi Ms

are there straight through replacements?
I have aftermarket header that are connected to the cats which are then connected to the Corsa.

I figure since there isnt a sniffer test here and my car is already running pretty rich....
I could just get rid of them