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JDean,

Greg is right on the money about how a cat can fail, but you might want to check one other thing out.

Cat converters run quite hot, and because of this, they usually have a thin sheet-metal heatshield riveted to their topside to protect the underside of the car. This shield is usually pretty thin and easily corrodes. When it does, it can start rattling pretty bad. Usually it rattles most at certain RPM points, especially when you're accelerating.

It doesn't mean the cat itself is bad. Usually, the heatshield can be ripped off with no problems. Just a suggestion...try taking it to a muffler shop to see if it's just the shield rattling. It might be the cat internals are toast, but this is worth checking...
 

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Doing it between 1st and 2nd gear sounds alot like the modus operandi of a loose cat heatshield.

This "debris in the converter" business sounds fishy to me. In order to prove that, to know it for sure, they'd have to take the cat off the car and visually examine the bed for signs of break-up.

If they do end up replacing the cat under warranty (not a bad deal if it costs you nothing), write down on the bill when you sign for the work that you demand to see the old unit from the car so you can see for yourself the guts.

Can you take it to a Speedy or Midas <*shudder*> exhaust shop to get a "second opinion" on it? The dealer says they "tightened" the heatshield...that, again, sounds fishy. Dealers are money making machines and are sometimes a bit overzealous to replace parts. I'd get the second opinion.
 

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_bullet_ride_ said:
I agree with mike in all respects...except one. NEVER EVER EVER EVER EVER TAKE YOUR CAR TO MIDAS!!! NEVER!!!!!!
Hehehe. True...that's why I put <*shudder*> after "Midas". I'd never get work done by that place but if you just need access to a hoist to look under it :D, maybe they can be trusted LOL
 
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