So about a week ago I installed the zzp catless downpipe and the catted midpipe combo. No lights went on and it drove fine for that week. I started the car one morning and I heard a difference in the sound. While driving the check engine like came on. I got it scanned and it was the P0420 code. The car seemed to drive a little different. Seems to be the car doesn't want to push and the rpms don't go past 4K. I did not get a tune for the downpipe and midpipe. Not sure if the BNR tune will help this problem or just get rid of the light. HELP!