I have 98 VW Jetta 2.0. Yesterday I noticed for the first time a loud rattling sound coming from under the car. I first thought it was perhaps the tailpipe or the muffler, but neither of them appear to be loose. My question is: Is this sound perhaps coming from the catalytic converter? I don’t even know if catalytic converters “go bad”; that is do they wear out need replacement every so often? Any suggestions are much appreciated.
D in AZ
It is possible for a catalytic converter to go bad and start rattling, but it doesn’t happen very often. The most likely cause of your noise is a loose heat shield. A strap clamp or a little bit of welding will solve the problem for around $20 at most good repair shops.
Or maybe just remove it, depending on which shield it is.