I have an 03.5 msp and i keep having problems with bucking and hesitation in the higher rpms, the ecu is not flashed, all i have is an injen cold air intake, i just changed out the plugs to denso iridiums today and that helped a little bit, the plugs i pulled out today were bosch platinums and they had carbon on them so i dont know if that tells anyone anything, the car also bobs a little bit between 700 - 750 rpms, i dont know if this is common idle for a msp, i just recently had the wastegate waranteed so that is brand new, i have also checked all of the vaccuum lines all over the car, the car is boosting around 8 psi, if anyone has some suggestions they are very much appreciated, thanks.