Power Steering Pressure (PSP) Sensor
WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 2006 Mercury Mountaineer, 2006 Mercury Monterey, 2006 Mercury Montego, 2006 Mercury Milan, and 2006 Mercury Mariner. However, it is still accessible from the selected car via links, so may be relevant.
The PSP sensor monitors the hydraulic pressure within the power steering system. The PSP sensor voltage input to the PCM changes as the hydraulic pressure changes. The PCM uses the input signal from the PSP sensor to compensate for additional loads on the engine by adjusting the idle RPM and preventing engine stall during parking maneuvers. Also, the PSP sensor signals the PCM to adjust the transmission electronic pressure control (EPC) pressure during increased engine load, for example during parking maneuvers.