Abstract: A fuel filler door actuator is provided having a locking arm and an alternate action mechanism. The locking arm is selectively driveable by an electric motor to engage or disengage with the fuel filler door of an automobile. The alternate action mechanism, including a spring-biased plunger having a cam track with a cam follower riding in the track, is engageable by and mounted adjacent to the fuel filler door and is capable of linear movement with respect to the door by alternating between an inward recessed position and an outwardly extended position each time an inward force is applied to the door. In the event of a loss of electrical power to the actuator, a manual override mechanism is provided which allows unpowered opening of the fuel door.