This paper proposes a novel communication timing control for wireless sensor networks, named Phase Diffusion Time Division method. This is based on the mutual synchronization of coupled phase oscillatory dynamics with a stochastic adaptation, according to the history of collision frequency in communication nodes. Through local and fully distributed interactions in the communication network, the coupled phase dynamics self-organizes an efficient time division pattern of the communication so that the network reduces the collision frequency by diffusion of the phase pattern, while it sustains sufficient throughput of the communications. We introduce the built-in virtual node dynamics model for sensor device, to implement impulse signal based interactions. This method is designed for applications in a regular grid model of the wireless network, but it can be extended to an irregular grid model as simulation results illustrate, where the proposed method outperforms CSMA method in the efficiency.