回复："part could cost up to $1k"

原厂配件会比OEM的贵多了。Remember that dealer needs to make a profit to "feed" the employees working there.

如果你的小老婆是california-spec的排气系统，catalyst converter会贵些。

Go back to the same shop and have them take a look. The part should have warranty (1 yr or 5 yr?). They could put in a new one if the original converter was defective. But you still have to pay for the labor of putting up the new converter.

$400 for catalyst converter job sounds too cheap. The retail price for catalyst converter is over $300+. The shop usually adds 10-20% markup on parts.

Good luck and let us know how it goes