But they cause a host of problems and the cause of many others along with codes not related to th o2 system.
I might just be lucky with it, but I've only had one "catalytic system" code thrown over the years, and that was due to a clogged fuel filter on a car that had sat for about 5-6 months. Even my 300K mile Civic has never thrown a catalytic system code, or any other code for that matter, so I'm not really sure what host of problems they cause. Care to elaborate?
