Power Rack & Pinion: Description
Power steering is a hydraulic-assisted rack and pinion unit with internal valving to direct fluid flow. The power steering pump is a vane type pump. Output pressure is regulated by a control valve located in pump housing.
A Power Steering Pressure (PSP) switch is located in the hydraulic line between power steering pump and rack and pinion unit. See Fig 1 . PSP sends a signal to Powertrain Control Module (PCM) to increase idle speed when necessary.