Accelerator Pedal Position (APP) Sensor
WARNING: This page is about a different car, the 2004 Ford RV Cutaway, 2004 Ford Econoline, 2004 Ford E450 Super Duty, and 2004 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
The accelerator pedal position (APP) sensor is mounted on the accelerator pedal on diesel applications. The APP detects the position of the accelerator pedal and inputs this information as a voltage to the powertrain control module (PCM). The PCM uses APP sensor information to aid in determining line pressure, shift scheduling and TCC operation. Failure of this sensor will cause the transmission to operate at higher line pressure to avoid damage to the transmission. This higher line pressure causes harsh upshifts and harsh engagements.