Marbles in exhaust???
Safety Car
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From: Jersey Shore Exit 98
Last edited by Jims79; Dec 9, 2008 at 01:29 PM.
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The C5 manual tranny makes a marbles in a can type noise upon low acceleration. If that is how you are driving and you have a 6-speed, it could be the tranny. If you do more spirited driving, it could be the exhaust.
Burning Brakes
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They even show a car slowly accelerating.
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Rattlin Decon!
When I pulled my catbacks off last spring, once off I could hear this rattling sound coming from inside the mufflers. I turned them from side to side and kept shaking them and these small brown pellets kept fall ing out. These pellets were once bluish green Decon mouse pellets, that I had in my garage to kill any field mice that might wonder into the garage, durring the winter. Guess where they decided to hoard them? I now use snap type traps and so far this early winter, have gotten 5 or 6 of them little buggers! Good luck trying to find your rattle.
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Are you sure you're not confusing exhaust noise for the noise the torque tube makes when you first take off? Both of the 6 speed C5's I have owned will occasionally make that sound when you come out of first gear very lightly from a stop.
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Sounds like possible cats to me. I have seen them fail in a car with <10K miles.
Instructor
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My cat on my Z28 makes this rattle at idle sometimes. Sounds just like marbles rolling around in a coffee can. Does it have a heat shield that could be rattling? If not, the "honeycomb" inside the converter could have worked loose and started vibrating inside the shell. I've been thinking about wacking the bottom of the cat with a hammer to pin it back in place
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Chipmunk could've gotten in there and stored some acorns. Happened to a muffler I had lying around in the garage!! I shook it out and a load of acorns fell out!
Le Mans Master
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From: Belleville Il
! Looked like a clown car cannon!!! About 20 of them blew out the back when i hit the gas,,,my boy was almost doubled up in laughter!!!:ch eers:
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Instructor
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From: Odenville Alabama
Cool
Muffler bearings!! I just bought four of them for my car. (Or so my wife thinks so) I needed four of them. Two for the cat converters, and two for the mufflers. Also had to buy the removal and installation tool. Did you know it takes a special grease to install them? Man that stuff is high dollar!! Also had to have them shipped by truck (hazardous materials you know) Them muffler bearings can get pretty costly. Hope no one else has this happen to you unless you need to buy a new Borla system and need to figure out how to get past the little lady. (If so this should do it) I think all together this should run around 1500.00
All kidding aside I think it is a piece of honeycomb that has come loose in the cat. Guess I'm off to the muffler shop unless this is something I can do myself. Anyone done this themself?
All kidding aside I think it is a piece of honeycomb that has come loose in the cat. Guess I'm off to the muffler shop unless this is something I can do myself. Anyone done this themself?
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From: Southern New Jersey, The wet part at the bottom
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Here's my $.02 on this one. Before going off the deep end on this (sounds just like a loose baffle), check that the hanger springs that support the X pipe aren't "jingling" as that was my noise that sounds like what you're describing. The fix is to bend the brackets as to take slack off the springs and keep them loaded (you'll need to get the car on a lift to do this). Lemme know how you make out.
Safety Car
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From: Jersey Shore Exit 98
My cat on my Z28 makes this rattle at idle sometimes. Sounds just like marbles rolling around in a coffee can. Does it have a heat shield that could be rattling? If not, the "honeycomb" inside the converter could have worked loose and started vibrating inside the shell. I've been thinking about wacking the bottom of the cat with a hammer to pin it back in place
you may breakup the honeycomb filter inside the cat & you will be buying a new one. I was hitting a cat to remove from a C3 and did just that.