A new fuel injection system with a solenoid actuator was developed to reduce jet stabilization times and was compared to a conventional fuel injection system using a fast-acting valve. The jet stabilization time was examined from free-jet images obtained using a flow visualization technique. Using a supersonic wind tunnel, the jet establishment image and trajectory for supersonic flows were obtained. The jet stabilization times were obtained at fuel tank pressures of 500, 700, and 900 kPa and injection orifice diameters of 1 and 2 mm. For all cases, the jets were stabilized at 4-12 ms, which was shorter than the stabilization time (approximately 300 ms) of the conventional system. The injection pressure measurements and jet trajectory comparison showed that the new system could inject fuel at the target pressure more effectively than the conventional fuel system.