Cat problems --C6Z
Thread Starter
Instructor
Joined: Apr 2006
Posts: 163
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From: Santa Monica CA
Cat problems --C6Z
I have deformation issue w/ my catalytic converters and wonder if anyone else has encountered it/knows of a solution. Apparently, the cats have deformed slightly, and the connection to the intermediate exhaust pipes (two large yokes) have rotated upward toward and in close proximity to the tunnnel plate (just above the connection) making a lot of banging noise upon hard acceleration.
The dealer denied warranty coverage for the cats as I have a Corsa H or X pipe and exhaust. The dealer thinks the exhaust has created too much heat at the cats and this has caused the deformation. The service manager was very understanding (and didn't buy that explanation himself) but his hands were tied by GM.
Anyone encounter this? Any fix? For now, the cats were heated up and bent downward away from the tunnel plated --but I suspect the pipes will curl upward again.
Thanks
Matthew
The dealer denied warranty coverage for the cats as I have a Corsa H or X pipe and exhaust. The dealer thinks the exhaust has created too much heat at the cats and this has caused the deformation. The service manager was very understanding (and didn't buy that explanation himself) but his hands were tied by GM.
Anyone encounter this? Any fix? For now, the cats were heated up and bent downward away from the tunnel plated --but I suspect the pipes will curl upward again.
Thanks
Matthew
Burning Brakes
Joined: Apr 2004
Posts: 1,022
Likes: 102
From: Sarasota FL
St. Jude Donor '13
I had a problem like that with my car when I put on the Fusion exhaust. The problem didn't show up until after I took off the Fusion exhaust and put the stock exhaust back on. ( The Fusion was too loud for me ) Under hard throttle you would get this loud awful sound from under the car.
I couldn't figure out was was causing the noise so I posted the problem on the forum and someone told me they had a problem like that and told me to see if the flange might be hitting the tunnel plate. I could see it was VERY close but not hitting when the car was on the lift. I put black magic marker on the tunnel plate above the flange and after a little driving I could see that the marker was worn off in the area it was rubbing.
To answer your question the way I fixed it was to loosen the bolts on the flange and put a pry bar between the flange and the plate and pry down while I tightened the flange. ( I had a friend help me ) It only takes a slight adjustment of the pipe to solve the problem. I can't say if that will fix yours as you have a aftermarket H-pipe and my exhaust was put back to completley stock but it is worth a try, good luck.
John
I couldn't figure out was was causing the noise so I posted the problem on the forum and someone told me they had a problem like that and told me to see if the flange might be hitting the tunnel plate. I could see it was VERY close but not hitting when the car was on the lift. I put black magic marker on the tunnel plate above the flange and after a little driving I could see that the marker was worn off in the area it was rubbing.
To answer your question the way I fixed it was to loosen the bolts on the flange and put a pry bar between the flange and the plate and pry down while I tightened the flange. ( I had a friend help me ) It only takes a slight adjustment of the pipe to solve the problem. I can't say if that will fix yours as you have a aftermarket H-pipe and my exhaust was put back to completley stock but it is worth a try, good luck.
John
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Wasn't Corsa a GM-licensed product that was sold at dealerships??Any exhaust system downstream of the cats should not affect warrant repairs. Cat have a longer warranty because they are covered under the emissions systems part of the vehicle warranty.
GM being in deep financial doo-doo may be trying to save money by using any excuse they can come up with for denying warranty claims.
You should contact the GM Regional Office to get this resolved. Don't call the toll-free number shown in the owner's manual, find out from the dealer where the Regional Office is located and get their number. You can complain to them and ask that they inspect the cats and review the denial by the dealer.
Was it the General Manager that denied the warranty work? If the Service Manager didn't go along with the decision, then somebody above him in the dealership made the decision, not GM.
I just don't buy the heat excuse. Cats need heat to work properly.
Melting Slicks
Joined: Sep 2003
Posts: 3,031
Likes: 74
From: If you don't weigh in you don't wrestle Road America
Here is what's posted on GM's website for Accessories.
If it's Corsa it should be just fine, sometimes just a different dealer will give you better service.
Another option would be to call Corsa and talk to someone there, after all you are their customer, I'm guessing that they wouldn't like to hear that GM is blaiming them for something that isn't there fault.
Cat-Back Exhaust System
This available dealer-installed Cat-Back Exhaust System(1) empties into four highly polished stainless steel exhaust tips that feature the Genuine Corvette Accessories emblem.
(1) Installation of this part on a vehicle intended for use on public roads may violate federal, state or local laws and regulations regarding emissions and noise/safety requirements.
This available dealer-installed Cat-Back Exhaust System(1) empties into four highly polished stainless steel exhaust tips that feature the Genuine Corvette Accessories emblem.
(1) Installation of this part on a vehicle intended for use on public roads may violate federal, state or local laws and regulations regarding emissions and noise/safety requirements.
Another option would be to call Corsa and talk to someone there, after all you are their customer, I'm guessing that they wouldn't like to hear that GM is blaiming them for something that isn't there fault.
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Michael S. Palmer
Race Director
Joined: Sep 1999
Posts: 12,439
Likes: 920
From: CONCORD NC
doesn't the emmisions system have a federally mandated longer warranty????? I agree that a Cat-back system should not effect warranty, and I'd probably put the stock parts back on a hit another dealer. Contacting the EPA might alse be in order, assuming you are using legal parts throughout
