HOLY SHIT DUDE! No wonder your car isn't running well, you're probably running a 9:1 AFR. Your car is undoubtedly in limp mode, which just lets it dump asstons of fuel into the mixture to prevent damage. You MUST get a new O2 right now. This will fix a lot of problems. Then get it tuned to make sure you don't have any real problems with leaning out.

Good luck.