i changed the cat and everything is fine. I didnt change anymoreplugs or wires after the cat was changed.
They reset the check engine light and it doesnt come back on. do I still have to change anything else? why would the cat be bad in the first place? I dont wanna have to change the cat again because I didnt replace anything else....

 

I had a problem with my cat a while back but it caused my engine to overheat not misfire. did you ever find out what the problem was?