I'm not sure what your question is exactly... I'm guessing it's "how can i turn off the cel?" Well you've said it yourself, it's due to your 2nd o2 sensor (bank2) which lets the ecu know if your cat is doing it's job. Since there's no cat, Your Cel will always be on. Buy a highflow cat: No cel, legal, better for our enviroment and just as good.