That's just it, a lot of things can trigger that code it seems and I certainly don't want to replace the cat if it is not the cause of the code.
I was reading articles on Eastern Catalytics site, and they talk about air intake leaks causing this code. My ZX3 had a broken air filter box (when I got the car) and I just replaced it, and I'm curious to see if this solves the problem, but I'm not sure why it would. I don't really understand why leaky air intake should cause the code, I thought that even filtered air is pretty much unrestricted, so sucking a little unfiltered air, I'm not sure why this should matter unless it is causing the computer to add extra fuel which somehow triggers this code.
The other thing I don't get is why a bad downstream O2 Sensor would cause this code rather than triggering its specific O2 Sensor code.
Another question I have is that I was looking at direct fit replacement Catalytic Converters and I see some that specify they are a direct fit for my engine with an automatic transmission. My ZX3 is a stick, and I'm wondering if there is any difference in fitting a replacement cat, or why does Eastern specify that it is a direct fit for the automatic. I'm planning to call them and try to find out, but perhaps someone here already knows.