Quote Originally Posted by 2010AveoLT View Post
I've concluded that the bad Downstream o2 sensor I had replaced back in July 2014 (it actually manifested itself a year before, but I could not afford the new sensor due to being a broke college student at the time) contributed to the frying of my cat; but now I'm confused on which one is the actual cat: the one in the manifold (the one that is actually monitored by the Oxygen Sensors) or the one further back in the exhaust system.
Let's be clear about this: I had to replace the flex pipe with much effort involved, so I know what is there. The cat converter is NOT in the manifold section, which resembles a pot, and is attached by three stud bolts to the flex pipe. The cat is in the first exhaust pipe that extends reward of the flex pipe. If you don't believe me, try changing a flex pipe on this car and see for yourself. My OX sensor wasn't bad, and there was no reason for it to fail. Actually it came loose very easily compared to all the other exhaust parts. But if you F-ed around with your ox sensor or didn't install it correctly, that might have contributed to your problem.