How can I check if my Audi 80's catalytic converter is faulty?

I suspect that my Audi 80's catalytic converter may be faulty, but I'm not sure how to confirm this. What are some ways I can check and diagnose potential issues with my catalytic converter?

If your Audi 80 is experiencing a decline in performance, such as decreased power or unusual noises or smells, this may be an indication of a faulty catalytic converter. It's best to take your car to a trusted mechanic for a thorough diagnosis.