Think about it like this.... Jody, DP-Tuner has a tune called drive through. It's all about the timing of the injection. When you let out of the throttle, but the motor is still holding say 2000 rpm. The injection timing is functioning at idle, not 2k. Now weather or not it's advanced or retarded, I couldn't tell you. But this is my best guess as far as an answer. But it is completely normal. Mine does it too.