I have a 2013 Dodge Challenger Sxt 3.5 L V6. I recently installed a k&n hi flo intake and a cat back borla s type exhaust. After a month of daily driving my check engine light came on throwing the p0420 code. I only have 35,000 miles on the car so I don't believe that it is a bad Cat. After talking to some of my car buddies they believe that the air flow is throwing off the computer and that a tuner would solve the problem. Are they right? and if so would it be better for me to get the i3 or trinity.