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New Catalytic Converter...?

My mechanic (who does not do exhaust work, so I feel he’s pretty objective) suggested I have my muffler looked at, that it was “rattling”. I brought the car to the place (part of a national franchise) that he recommended, and they told me that the rattling was in fact coming from the catalytic converter, and that I would need a new one (around $800…), and that the Grand Caravan is not compatable with the “universal c.c.” But, he said, I should first find out the root cause of “unspent fuel” making it to the c.c. (that this is what’s causing the trouble) He also said that it may be several more years before the c.c. gives me any serious trouble–but that at some point it may not pass inspection.



Does this make sense?

Rattling catalytic converters may mean they’re breaking apart from the inside…it can also mean only that the heat shield around the converter is loose, which is quite common and doesn’t affect the converter’s performance in any way.

This place is trying to sell you a converter that you may not necessarily need, and how does the person telling you this know anything about “unspent fuel” reaching the converter? Was any diagnostic work done before this?

Walk away. This place is not to be trusted.

If the catalytic converter were that damaged internally, it would have caused a check engine light long ago. You don’t have said light, do you (and, have it code out to the catalytic converter)?
Wire, or a large band, wrapped around the cat will take care of a rattling heat shield.

I was told that it is not the heat shield; that the rattling is coming from inside the cc. I was also told that as the damage gets worse, that the “check engine” light will illuminate, then the root cause of the problem will be apparent.

I suggest having someone else check it.

BTW it would be really helpful if we knew what year Carvan you have and how many miles on it.

Sorry–It’s a 2002 with 98,000 miles.