The invention relates to a method for controlling an integrated starter-generator, including receiving a start signal; determining an initial position of a rotor with respect to a stator phase winding integrated starter-generator of the integrated starter-generator; applying a pulse-width-modulated signal to the stator winding corresponding to determined initial position of the rotor; measuring current of the stator winding in response to applied pulse-width-modulated signal to determine current variation; if current variation is more than a threshold value, determining updated rotor position and applying a pulse-width-modulated signal to the stator winding corresponding to the updated rotor position; determining speed of the rotor, if speed of the rotor is more than a threshold value, monitoring a trigger signal from an ignition trigger sensor coupled to the engine; and if the trigger signal is received, determining the updated rotor position and exciting the stator winding corresponding to the updated rotor position.