Wassup fellas. I'm having a weird problem and the so called pros in the area don't have any definitive answers for me. I have a check engine light and when I scanned it, it reads catalyst below efficiency. Bad cat right? no I just swapped in a magnaflow high flow cat 2months ago. I changed the o2 sensors and cleared the codes but they came back. Also my car is burning a lot of gas and is idling around 1100rpm. I cleaned the throttle body and checked for leaks and nothing. Anybody ever heard of this or have any ideas?

probably the o2 sensor. i read alot of people have problems w/ throwing codes when they install a hi-flow cat. i think you would need the o2 simulator

Yea same problem after I put in my high flow cat, but took a month for it to start for me.
I did this mod, which I had also had done before when I put a 3/8" hole through my stock cat. And both times it works.

http://www.j-body.org/forums/read.php?f=2&i=326648&t=309456#326648

So anyone know of a place to get an o2 simulator. And will this solve the burning gas problem and check engine light? Thanks for any and all help.