In general, this disclosure relates to techniques for automatically supplying a pressurizing unit (e.g., syringe) that is used with a powered medical fluid injection device with fluid. An example method performed by the medical fluid injection device includes obtaining operational state information of the medical fluid injection device, wherein the operational state information includes information other than a fluid delivery amount for a subsequent injection procedure. The example method further includes using the operational state information to determine whether the powered medical fluid injection device permits a fluid replenishment operation for the pressurizing unit. If the fluid replenishment operation is permitted, the method further includes automatically supplying the pressurizing unit with an amount of medical fluid. If the device includes multiple pressurizing units, the device may initiate an automatic fluid replenishment procedure for one or more of the pressurizing units during operation.
