An infusion pump for infusing fluid from a reservoir into a body of a user comprises, a housing； a drive mechanism including a motor and one or more drive components contained within the housing and operatively coupled to the reservoir to deliver fluid from the reservoir through a fluid path into the body of the user. The pump also includes one or more electronic components to take a series of measurements of a parameter associated with the motor or one of the drive train components； and a controller. The controller is contained within the housing, and is adapted to calculate a weighted average of the series of measurements by applying a weighting factor to each measurement in the series of measurements to determine a weighted value corresponding to each said measurement and calculating the average of the weighted values, determines the drive count of the motor, determines a drive count value based on the drive count of the motor, calculates a maximum threshold value based on the drive count value, compares the weighted average to the maximum threshold value, and determines whether an occlusion has occurred in the fluid path of the infusion pump by determining whether the weighted average is greater than the maximum threshold value.
