Sometimes the heat shields around the outside of the converter break loose or rust out and causes a rattle noise.
It s illegal to remove a catalytic converter.
Yes
bits of the catacomb that makes up your coverter have fallin losse. if it sound like there is dirt in it that that's the case. The catalytic converter needs replaced.
Depending on what kind of "whirring" sound you are referring to, it can either be your catalytic converter or some problem with the exhaust system. Most likely the catalytic converter if its what I'm thinking of.
Yes, it can and this may also be a loose or cracked converter heat shield.
YES IT WILL
No, but it will make a sucking type sound.
It could.It could.
I had this problem and tweaked the throttle and replaced the catalytic converter - fixed.
Usually a sputtering muffler means that a new catalytic converter is needed. The sputtering sound is the car misfiring.
Plugged catalytic converter
Check the heat shield on the catalytic converter Check exhaust hangers