interesting, well I found out my spark plug wires were swapped.. it was firing 1234. so I set them up right and someone said that if that too much hc would make the cat not work so I may have fixed it.
took it to the shop and it was twice as bad >.< just going to have them diagnose it..
and I thought c02 was a good thing to see and it was the three baddies that they'd fail you on. c02 is oxygen, no? co is carbon monoxides..