Sequential filling control by Computrol is a unique process perfectly suited for alternative fuel services such as transit and other fleet vehicles powered by CNG. Typically, at the end of their shift, drivers simply park the vehicle in an empty fueling stall and connect the fueling hose. They then “queue” the vehicle by presenting a keyfob or keying in the unit number at the Computrol cardlock station. Each vehicle in the queue is fueled up one at a time so that maximum pressure can be maintained in the line without overworking the compressor system. The programming has the provision to temporarily suspend the fueling queue so that designated “fast-fill” dispensers can be utilized to quickly fill vehicles without having to wait their turn in the queue. The system also accommodates vehicles that have been queued up but physically removed from the stall before they are serviced. It is designed to automatically resume operations in the event of a power failure and allows supervisors control over the queue should they deem it necessary. At the start of the next shift, the vehicles have been filled to capacity with CNG and the driver need only disconnect the fueling hose and drive away.