The present disclosure provides improved methods for calibrating the zero position of at least one drive member of an injector system is disclosed. Automated methods of position calibration of the drive member of a fluid injector are disclosed. These methods address sources of error in positional accuracy and fluid delivery inaccuracies, such as disposable syringe tolerance and injector wear over time. According to other embodiments of the present disclosure, methods and fluid injector systems for determining and correcting for the amount of slack in a fluid injection apparatus are described. An understanding of the calibration and the amount of slack in a fluid injection system allows a processor to correct for the slack, thereby ensuring more accurate fluid delivery to the patient and more accurate imaging processes.