I have a 1999 A6 Avant quattro. I have a rattling sound coming in the area of the catalytic converter and I had a check engine light come on and got the following computer code from my freinds diagnostic readed: code is P0432 - Main catalyst below threshold (bank2) that I reset, but I still have the sound which is getting worse.
Does this mean the catalytic converter is bad? How do you determine which converter is bad if their are 2 of them?
Please advise.