Abstract: A cycle control for plastic injection molding machines. All time-responsive machine controls are eliminated by initiating or terminating machine functions in response to actual, physical properties experienced by the machine or by the plastic or in the mold, rather than in response to elapsed-time intervals. Means are provided for changing the injection pressure to the holding pressure when the pressure in the mold cavity reaches a predetermined pressure, means are provided for ending the holding pressure and initiating the cold/cure portion of the cycle in response to actual, physical conditions of the plastic in the mold, such as pressure or temperature, and means are provided for opening the clamp to eject the molded part and thus end the cold/cure portion of the cycle in response to actual, physical properties of the plastic in the mold, such as pressure or temperature. The machine cycle is thereby completely independent of time, and cycle time may be minimized.