Mustang L4-140 2.3L Turbo VIN W FI (1984)
TRW Rack & Pinion
The control valve uses rotational motion of the input shaft and sleeve to direct fluid flow. When the steering wheel is turned, resistance of wheels and
weight of vehicle cause the torsion bar to deflect. This deflection changes position valve spool and sleeve ports, directing fluid under pressure to
appropriate end of power cylinder. The difference in pressure forces on the piston aids in moving the rack to assist turning effort. The piston is attached
to the housing rack and the housing tube functions as the power cylinder. The fluid in the opposite power cylinder is forced to the control valve and
returned to the pump reservoir. The control valve is forced back to the center position by the torsion bar when steering effort is removed. Pressure is then
equalized on each side of the piston and the front wheels return to the straight ahead position.
