Ever had a cat go bad???
Thread Starter
Racer
Joined: May 2007
Posts: 332
Likes: 1
From: Spokane WA
Ever had a cat go bad???
So lately Ive been getting a code (p0420) which is TWC system low efficiency bank 1. I clear it and it comes back within a 100 miles every time, so I decide its a cat or a sensor? I planned on swapping the rear sensors this weekend to diagnose further.
So I pull into the garage last night and hear this light clanging noise from the center of the car? I jack it up for a closer look and it sounds as if there are broken pieces inside the cat on the drivers side?
The car has 7300 miles and hasnt been driven much in the last 4 years.
Questions:
1.)Does this sound like a bad cat?
2) could lack of use be the reason?
3) Bank 1 is the drivers side correct?
4)Can you replace just one cat, or is it the whole center section?
5) Do you know anything about what GMs Federal emission catalytic converter warranty covers?
Thanks for any insights
So I pull into the garage last night and hear this light clanging noise from the center of the car? I jack it up for a closer look and it sounds as if there are broken pieces inside the cat on the drivers side?
The car has 7300 miles and hasnt been driven much in the last 4 years.
Questions:
1.)Does this sound like a bad cat?
2) could lack of use be the reason?
3) Bank 1 is the drivers side correct?
4)Can you replace just one cat, or is it the whole center section?
5) Do you know anything about what GMs Federal emission catalytic converter warranty covers?
Thanks for any insights
Team Owner
Joined: May 2003
Posts: 23,480
Likes: 9
From: East Meadow NY
St. Jude Donor '12
So lately Ive been getting a code (p0420) which is TWC system low efficiency bank 1. I clear it and it comes back within a 100 miles every time, so I decide its a cat or a sensor? I planned on swapping the rear sensors this weekend to diagnose further.
So I pull into the garage last night and hear this light clanging noise from the center of the car? I jack it up for a closer look and it sounds as if there are broken pieces inside the cat on the drivers side?
The car has 7300 miles and hasnt been driven much in the last 4 years.
Questions:
1.)Does this sound like a bad cat?
2) could lack of use be the reason?
3) Bank 1 is the drivers side correct?
4)Can you replace just one cat, or is it the whole center section?
5) Do you know anything about what GMs Federal emission catalytic converter warranty covers?
Thanks for any insights
So I pull into the garage last night and hear this light clanging noise from the center of the car? I jack it up for a closer look and it sounds as if there are broken pieces inside the cat on the drivers side?
The car has 7300 miles and hasnt been driven much in the last 4 years.
Questions:
1.)Does this sound like a bad cat?
2) could lack of use be the reason?
3) Bank 1 is the drivers side correct?
4)Can you replace just one cat, or is it the whole center section?
5) Do you know anything about what GMs Federal emission catalytic converter warranty covers?
Thanks for any insights
I wouldn't expect it to break so soon, but who knows. It could have rotted out.
Burning Brakes
Joined: May 2008
Posts: 1,147
Likes: 1
From: Mohegan Lake New York
You certainly could have a broken up cat (internally)can cause a whole host of problems,from overheating to just running hotter than normal to throwing all kinds of codes as the pieces flop around alternately blocking the exhaust flow.you can tap the ex. system w/a rubber mallet see if the rattle or noise is coming from the cat.I believe Chase is correct fed. warantee 80k/8yrs if cat is indeed bad when taken out examine if just broken other cat may be ok if melted and broken chances are other cat is bad also. you might want to take it to a good tuner after its repaired,just to make sure there isn't something that caused the cat to fail. good luck!
Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
my Cats go bad all the time. Frick'n little buggers, but my wife wont let me shoot them.
Oh Oh Cats on the car.... Yes that happend once when I drove over a rake. Darn tines in the rake punctures both cats. Had to replace them with High Flow cats
In many cases dirty fuel, old fuel and just plain a dirty engine in time will clog up the cats.
Why does this happen? 91 octane, vs 93 octane can make a big difference and taking too easy on a big V8 engine.
Go out and get on it. Burn the crud out of the engine and cats. Figure two full tank fulls of good hard driving.
Oh Oh Cats on the car.... Yes that happend once when I drove over a rake. Darn tines in the rake punctures both cats. Had to replace them with High Flow cats
In many cases dirty fuel, old fuel and just plain a dirty engine in time will clog up the cats.
Why does this happen? 91 octane, vs 93 octane can make a big difference and taking too easy on a big V8 engine.
Go out and get on it. Burn the crud out of the engine and cats. Figure two full tank fulls of good hard driving.
Last edited by AU N EGL; Apr 10, 2009 at 11:23 AM.
Melting Slicks
Joined: Oct 2007
Posts: 2,798
Likes: 8
From: It's true money can't buy happiness, but it is more comfortable crying in a Corvette than on a bicyc
St. Jude Donor '13
I've had them start rattling. I've also melted the front of them sealing off a lot of the holes. I'd take it to the dealer cause it may be under the Federal mandated warranty for the emissions system. If they want to charge you run, run away fast. Your A$$ will bleed when they're done with you. It's a good excuse to swap to Hi Flows. Or if you stretch the truth about life and limb you could do the whole system with Long Tube Headers, Hi Flows, and an X Pipe.
The rattling can occur from many reasons. Even submerging a hot cat under water can do it.
The rattling can occur from many reasons. Even submerging a hot cat under water can do it.
Burning Brakes
Joined: Nov 2006
Posts: 880
Likes: 0
From: Detroit Area Michigan
One went bad on my son's Camaro SS. I got under the car with a stethoscope to make sure. watch your ear drums! Anyway, the dealer fixed it for free to me, but the bill said $515.01, It had 74,900 miles. Good Luck ....bob.
Thread Starter
Racer
Joined: May 2007
Posts: 332
Likes: 1
From: Spokane WA
my Cats go bad all the time. Frick'n little buggers, but my wife wont let me shoot them.
Oh Oh Cats on the car.... Yes that happend once when I drove over a rake. Darn tines in the rake punctures both cats. Had to replace them with High Flow catsIn many cases dirty fuel, old fuel and just plain a dirty engine in time will clog up the cats.
[/I]Why does this happen? 91 octane, vs 93 octane can make a big difference and taking too easy on a big V8 engine.
Go out and get on it. Burn the crud out of the engine and cats. Figure two full tank fulls of good hard driving.
Oh Oh Cats on the car.... Yes that happend once when I drove over a rake. Darn tines in the rake punctures both cats. Had to replace them with High Flow cats
In many cases dirty fuel, old fuel and just plain a dirty engine in time will clog up the cats. [/I]Why does this happen? 91 octane, vs 93 octane can make a big difference and taking too easy on a big V8 engine.
Go out and get on it. Burn the crud out of the engine and cats. Figure two full tank fulls of good hard driving.
Only two? Lol
The car sat for a long time and was never driven hard. (Untill me)
The dealer says no problem on the warranty. They will actually replace the whole assembly, so you get two for the price of one. I wont pay for stock cats, so if GM doesnt, Im gunna get my LG LTs sooner rather that later.
Last edited by KRISCO; Apr 11, 2009 at 12:21 AM.
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Team Owner
Joined: Sep 2003
Posts: 43,084
Likes: 33
From: Raleigh / Rolesville NC
at the time I was not married to her, when I drove over the rake tines. Met my current wife in the local corvette club three months later. She already had her own C4.
Well more the two tanks would be best. Driving your vette at WOT with 93 octane or hopefully 91 octane will burn all the crap and carbon build ups. That is something many ppl just dont get.
Well more the two tanks would be best.
Driving your vette at WOT with 93 octane or hopefully 91 octane will burn all the crap and carbon build ups. That is something many ppl just dont get.
Burning Brakes
Joined: Mar 2003
Posts: 1,156
Likes: 2
From: Arlington VA
If you can get the car up on jack stands, get up under the car with a rubber mallet and lightly tap on the various exhaust components. IF something is broken up in the cat, you will hear it.
