my car seems to bog down when i push down on the throttle I think its getting to much gas also my ce ligkt is on it gives me 21 twice

 

Code 21 is an O2 sensor probably the one in the manifold there is a 2nd one after the catalytic converter.

If you use a code reader it will tell you which one is bad

 

in order to cause the car to bogg down it will most likely be the 02 sensor in the manifold that owuld be bad

 

XO, "I concur"

 

I replaced that one twice I thought that I got a bad one the first time but I was getting I diffrent code then. this code came on about a week after I put on a new cat I thought I might have pulled I wire loose or something but I dont know what tools I need to test the wires going to the o2 or witch is pos and neg when I had auto zone run a code check on it today and they said it is basicly saying the o2s are not there what wire goes to both of them

 

Check your wiring to the sensors.