Catalytic Converter

[Mitch Wolberg <rkane@domain.elided>]

I think I've got a bad catalytic converter on my commuter car (125k).
The exhaust started rattling several months ago and replacement of the
exhaust from the cat-back didn't help. I took some time this weekend
looking for possible rubbing or a loose heat shield but didn't spot
anything. Now the gas mileage has started to drop despite a recent tune
up. Any way to diagnose the cat or do I have to steal some money from my
Alfa budget, Alfa content ;), and buy a new cat?

Thanks,
Mitch Wolberg,
69 Duetto Jr. - no cat here

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