As I stated previously, you do not need a tune. I was quoted by one of the only people willing to tune our cars, "that is was totally a waste of money and their time." As for the pedal position sensor, I tend to agree with the code, but I have seen that code not be acurate. I have 2 xfires and one with 500,000 miles. So I have seen it all. By the way neither have been to a repair shop for anything, but clutch replacement. And good luck replacing the sensor or maybe the entire accelerator pedal. I don't know which it is? Maybe the pedal.