I am trying to get my car through the marta(tenn emission) and it keeps failing. I recently did a tune up on the car and it still fails badly. From the paper, the co and the other part that they test is high. On the car i have a high flow cat, 10.2 wires, and that is all the performance things i have done to the car mechanically. can someone help me with this.

 

what is "the other part they test"? They usually test HC, CO and NOx. Mine failed NOx and it turns out the timing was way ****ed up, but it wasn't the timing belt. The distributer cap button had become retarded and it needed to be replaced because it was stripped out.

First thing I would check would be the timing belt, it's easy to look to see if the marks on the belt line up with the marks on the cam gear. If they do, pull the dizzy cover off and see if that is still lined up proper. Then go to your O2 sensor and pull it, make sure it's not gummed up with carbon or broken, if it is, replace it.

Also, before going to get the emissions tested, drive it around for at least 30 minutes and drive it hard right before you go to do your test. When I finally passed my emissions, I had driven it hard for about 5 miles and when I pulled up I kept the Tach needle at 2000RPM right until the guy opened the door to take over and pull it in because in this cold weather the catalytic converter can get cold really fast and stop catalyzing the exhaust chemicals properly

 

You really need to post the emissions readings exactly as they are printed on the sheet they gave you before anyone can help you.