ok i have done everything i can think of, i am out of ideas. ive changed my plugs, plugwires,new fuel filter, i put some LUCAS fuel injector cleaner in it, and its still running like crap. even after all this i took it back to advance auto to get it checked AGAIN, and it threw the same codes, it threw the O2 sensor codes, both of them, because of my cat bein gutted, and it threw the code random/multiple cylinder misfires. now im thinkin its a coil pack.im completly out of ideas. please someone help?

 

and im pretty sure my o2 sensors are completly fried. would that mess anything up? some ppl have tld me that if the o2 sensors are bad, it will cause what my cars doin, and some ppl have tld me that the o2 sensors will do nothing but throw a code the the computer and make the SES light to come on

 

You pretty much answered your own question right there, whether you know it or not.
I don't know the year of your car, but I'm gonna presume that you also have an O2 sensor after the cat. The O2 sensors are part of the fuel management system. They read the oxygen content in the exhaust gases and adjust fuel output accordingly to keep the oxygen level within specs. Gutting the cat confuses the ECM because it can't adjust the fuel delivery to get it back into spec, and then the SES light goes on. So what's happening to you is the computer is adjusting the fuel mixture back and forth trying to get it right, which is why you get your cylinder misfire code. The easiest thing to do at this point would be to get an after cat O2 "fooler" sensor. Places like Summit or JEG's probably have one.

 

Which O2 sensors? The two sensors in the manifolds adjust measure air/fuel ratio and adjust fuel trims accordingly. The ones monitoring the cat serve only that purpose.

 

the computer i hooked it up to advance said its both of them

 

camaro 69, so what ur saying is i dont have to go out and buy a whole new factory cat and some new o2 sensors right?

 

oh yea and its a 2000 3.8 V6 camaro btw...

 

You have three O2 sensors... One in each manifold, and one after the cat. Was it Bank 1 Sensor 1, Bank 2 Sensor 1, or Bank 1 Sensor 2?

 

the guy at advance said it was the "downward" o2 sensor, so im guessing hes tlkn about the sensor after the cat...

 

Then that one has nothing to do with the air/fuel ratio or fuel trims. It's only purpose is to alert you that the cat is not performing up to standards. If you get a O2 simulator, it will tell the PCM that the cat is good, so the check engine light should disappear. Or you could have someone tune the codes for that sensor out. Your misfire has to do with something else. I would ask him which one it is specifically. If it is one of the other O2 sensors than that could be the problem.