The car wasn't exactly stock when I sold it. And with the cat being directly connected to the header, and the combination of some serious ECU tuning(REQUIRING 92 octane), somehow the cat caved into itself and got completly plugged. Maybe melted was the wrong word. It suffered catystophic thermal breakdown in one way or another. When the cat got plugged, it started plowing off all the emissions sensors and hoses on the engine. It was actually running and exahausting through the EGR valve. Weird shit. That's why I have a rotary now, I understand those.