Steering: Description and Operation

DESCRIPTION
The power steering system uses hydraulic pressure generated by the power steering pump to reduce the force required to turn the steering wheel. The power steering system has a typical rack and pinion design consisting of the following components:
^ Steering column.
^ Power steering pump.
^ Power steering pump reservoir.
^ Steering gear.
^ Front wheel spindle tie rods.
^ Tie rod ends.
^ Interconnecting hydraulic tubes and hoses.
The steering gear includes the following:
^ Power steering line connections.
^ Power steering left turn pressure hose.
^ Power steering right turn pressure hose.

MECHANICAL OPERATION
The steering column shaft, the steering column intermediate shaft coupling, and the power steering gear input shaft and control transfer the rotary motion into side-to-side motion. The front wheel spindle tie rods and tie rod ends connect the steering gear sector shaft to the front wheel knuckles. The front wheel knuckles convert the side-to-side motion into the turning of the wheels.

HYDRAULIC MOTION
The power steering pump, which is driven by the crankshaft through a drive belt and pulleys, develops the hydraulic pressure necessary to operate the system Fluid is drawn into the vane-type power steering pump from the power steering pump reservoir when the engine is running. Hydraulic fluid is pressurized by the rotation of the rotor and vanes and is forced into the steering gear When the steering wheel is turned, the steering gear converts this hydraulic pressure and flow into mechanical motion that will move the front wheels in the direction of the turn.

POWER STEERING PRESSURE (PSP) SWITCH
A power steering pressure switch (PSP), located on the power steering pressure hose, is normally closed. As the power steering load increases, the PSP switch opens and signals the powertrain control module (PCM) to increase the idle speed.