A liquid pump includes an electronically controlled throttle inlet valve to control pump output. With each reciprocation cycle, a plunger displaces a fixed volume of fluid. When less than this fixed volume is desired as the output from the pump, the electronically controlled throttle inlet valve throttles flow past a passive inlet check valve to reduce output. As a consequence, cavitation bubbles are generated during the intake stroke. Cavitation damage to surfaces that define the inlet port passage are avoided by a specifically shaped and sized cavitation flow adjuster extending from the valve member of the passive inlet check valve. By positioning the cavitation flow adjuster in the inlet port passage, a flow pattern is formed in a way to encourage cavitation bubble collapse away from surfaces that could result in unacceptable cavitation damage to the pump.