01 Formula runs rough when hot. HELP!
On the other hand, the cat may be clogged for other reasons (melted material inside the cat no longer passing exhaust), or the issue may be totally unrelated. If you have an IR gun, you can check cat temp to see how it compares to the other bank (cat temp should be between 450-600°F, depending on where you take the temp).
Or, the issue may have nothing to do with the cat(s) at all. A fuel related problem (low pressure, lean mixture) can also create the issues you have described.






