A method tracking positive displacement efficiency of a high pressure positive displacement pump in a hydraulic regulator system of a turbomachine delivering a flow rate based on an engine speed of the turbomachine, the flow rate delivered to an actuator actuating variable geometry vanes of the turbomachine and to a bypass valve feeding engines of the turbomachine, the method including: starting engines of the turbomachine at a low engine speed, the valve being closed; using a computer to order a movement of the actuator; progressively increasing the engine speed until the flow rate reaches a predetermined value sufficient for opening the valve; storing in the computer a position of the actuator and the engine speed corresponding to opening of the valve; repeating the preceding operations at successive instants during a lifetime of the engines; and replacing the high pressure positive displacement pump when the engine speed exceeds a predetermined value.