I HAVE A 2001 COBRA THAT IS DRIVING ME CRAZY. MY CAR HAS BEEN RUNNING RICH FOR 6 MONTHS. TESTING COMES UP THAT IT IS A O2 SENSOR. I HAVE HAD A SHOP CHANGE THEM OUT AND IT STILL DIDNT FIX THE PROBLEM, SO THE OLD ONES WERE PUT BACK ON. AT FIRST THE CODES SAID THAT THE COILS WERE BAD OR MISFIRING SO I CHANGED OUT THE WHOLE SET. COULD THE PROBLEM BE THAT I PUT A X-PIPE ON AND REMOVED THE CATS? IF SO HOW DO I FIX THIS PROBLEM. THANKS.