Had the same issue I think with my truck, I had a hollow knock at idle. Nothing would quiet it up.It sounded like a rod knock and I hada big loss in power and fuel mileage. No codes, took all my add ons off which included Edge Ez, Rokktech crank sensor,Afe stage IIand there was no difference. Took the truck into the dealer because I finally got a code P0071. Dealer said they had a reflash for everything I complained about and the code. This was very hard to believe, but when I left the dealer it was a whole different truck again. There are days that I feel like the truck is acting up again, but I have never heard the knock again, ether I'm getting used to the power of the truck or its a dog again? I don't haveanother Cumminsto compare it too. I put my aftermarket stuffback on one by one with the AFE being last and to me that really seemed to kill the torque.