Abstract: A pressure differential motor control system for controlling a motor of a high volume low pressure (HVLP) spray system via a pressure differential. The pressure differential motor control system has an outlet fitting connected to a turbine assembly, and a pressure switch adapted to be activated by a pressure differential from the outlet fitting. The outlet fitting has a first section connected to the turbine assembly, a mid section featuring low and high pressure ports, a second section connected to a quick coupler hose and spray gun, and a venturi defined through the outlet fitting. The low pressure port is in communication with the venturi, and the high pressure port is in communication with the input side of the outlet fitting. The pressure switch is activated by a pressure differential from the low and high pressure ports of the outlet fitting, thereby sending a signal to a motor controller for controlling a motor of the turbine assembly.