Throttle Position Sensor - code P0221

I recently purchased a 2009 A3. I absolutely love it (having switched from an expedition I passed to my 16 year old for his birthday - BIG change). It has always had very slight jerkiness from take off and stopping but it seems just like an older BMW I had (kind of go-cartish) so I didn't think anything of it. Three weeks in the EPC light came on and I had sluggish power in the first few gears. I could push over to manual and quickly get to 4th gear and be okay, made it home. Poked around on here and saw a "let it sit" theory, which I did. Took it out a few hours later and EPC light came back on, as well as the engine light. I took it back to the dealer the next day and they said it was the throttle sensor, ordered the part and fixed it for free. Now, three more weeks later, the EPC light came on early in the week, same issue, loss of power. Turned car of and let it sit. Through the week it has been fine but yesterday on my way home, same thing, including engine light. Pulled into Autozone to have code read and got "P0221 Throttle Position Sensor". Engine light but no EPC light was on this morning and then went off after leaving daughter's school and car is driving fine. What the heck is going on? I drive all over creation for kid's sports tournaments and am super nervous now about getting stranded 400 miles away from home. Any suggestions?