Abstract: A method and system of adjusting a drive signal to a fuel injector or other electromagnetic device having an electromagnetic coil and an armature. The system includes an amplifier coupled to the electromagnetic coil by a link. A sensor is coupled to the link to measure the electric signal travelling through the link and produces an output signal based on the sensed electric signal. A controller coupled to the amplifier and to the sensor produces a drive signal for the electromagnetic coil. The controller determines the position of the armature based on the output signal of the sensor, and modifies the drive signal based on the position of the armature. The method includes sending a drive signal to a fuel injector, sensing whether the armature contacts the body of the fuel injector, running the injector with the drive signal if no contact is detected, and upon sensing contact between the armature and the body, modifying the drive signal.

Abstract: A fuel injector assembly including a body portion, a valve seat fixed relative to the body portion, a valve member movable relative to the valve seat, an outer layer substantially surrounding the body portion, and a damping material between the body portion and the outer layer, the damping material cooperating with the outer layer to dampen noise and vibration produced during operation of the fuel injector. Preferably, the fuel injector also includes an electrical connector mounted on the body portion, and the damping material is adjacent the electrical connector. In the preferred embodiment, the damping material is a viscoelastic material.