ive got an 05 gt with a CAI, underdrive pulleys, CMC Deletes, and JMS 93 performance tune with 4:30 gears. The car has run great until a few days ago i noticed that at idle it has a miss in the exhaust note. At WOT from 3rd gear up at 4000+ rpm the car starts jerking and missing really bad. the ford dealer put it on the computer and said that that everything checks ok except he noticed that the right engine bank was running twice as rich as the left. my first thought is an O2 sensor but no codes are being thrown. Ive got less than 20000 miles on the car and i always baby it. please help me!