A remote pressure-controlled three-way valve device has a plunger axially traversed by an inlet passage normally closed by a spring-urged inlet valve. The plunger's outer sidewall has a recess in which an O-ring extends to abut against the steps of the recess to limit the plunger stroke and keep an outlet passage closed to a venting port formed in the sidewall of the body of the device. O-ring prevents short-circuits between the inlet passage and the vent port and a spring for counteracting friction between the O-ring and the device inner wall. Filters arranged in respective ports connectable to the input air-pressure supply and the tire inner tube provide fixed seats for the springs to bear on. The plunger may dwell in a stable intermediate position that opens the outlet or deflation passage is controlled by sending an air pressure through the inlet port at 50% of the normal pressure.