Which cats usually go first. I've replaced the main cat but the old one looked good. The car runs okay at times but seems plugged other times.Could it be the
pre cats?

 

Y E S . Gut Those Cats. And Get Ur Power Back .

 

lol, I never got my seven with a cat, it came with the presilencer and downpipe already installed. You guys are always talkin about 'guttin' them. So what do you mean?

Take it off, and shove an iron rod in there and dig all that **** out? Is it like a honeycomb type filter inside there?

 

just buy headers or a downpipe... or make your own but hell i dont have room to talk, i still got the stock exhaust on trying to get this damn car to pass the smog test..