A fuel system for an internal combustion engine includes a fuel system, a valve train, and a fuel injector including a cam actuated plunger. The fuel injector has a noise suppressor fluidly connecting a plunger cavity to each of a spill passage and a nozzle supply passage in the fuel injector. The noise suppressor has an inlet configuration forming a fuel admission flow area to the plunger cavity, and an outlet configuration forming a fuel discharge flow area. The fuel discharge flow area is smaller than the fuel admission flow area, and the noise suppressor adjusts to the outlet configuration to throttle discharging of fuel from the plunger cavity to limit valve train noise.