Does the check engine light come on? TBW systems default to idle, or just slightly over it, anytime a fault is detected. A fault should be accompanied by a code and engine light. Sometimes a code set in a pending status and doesn't turn the light on unless the fault happens again within a certain time period. Take it somewhere and see if they can get a code out of it. It sounds like there is probably something going on in the pedal position sensor when you move the pedal quickly. This is what warranties are for, I suggest using yours. This stuff can get pricey and even if the dealer can't find something wrong now you will have it on record as a problem in case it causes you problems down the road.
2012 Silver Sport S, Silver, 6 speed, soft top, 3.73s, LSD, PCG, Infiniti, deep tint windows, Pro Comp 1028 wheels, 33" Duratracs, Smittybilt bumpers and steps, KC fog lights, Mopar slush mats and fuel door.
Happiness is a belt fed weapon.