A valve lift sensor detects the position of an engine valve. The valve lift sensor includes a movable target carried on an engine valve and a stationary coil carried within an engine valve assembly. A signal generator energizes the coil with an oscillating voltage to create an oscillating magnetic field, which is concentric to the coil for inductive transfer with the target. A comparator compares the voltage from the signal generator with the voltage at the resistor to determine the phase lag of resistor voltage relative to signal generator voltage and indicate the engine valve position. Using the phase lag, the comparator provides a pulse-width-modulated signal with a duty cycle proportional to the valve lift to an engine valve control operable to control the operation of the engine valve.