PEDAL FREE PLAYThe amount of brake pedal
movement before braking action begins to take
PEDAL HEIGHTDistance of the brake pedal
above the floor of the vehicle.
PICKUP COILComponent that sends pulses to the
control unit of an electronic ignition system as a
result of trigger wheel action.
PICKUP COIL AIR GAPThe space between the
pickup coil and the trigger wheel tooth.
PILOT BEARINGThe bushing or bearing that
supports the forward end of the transmission input
PINION GEARDifferential gear turned by the
drive line. It meshes with the ring gear. Also, a
gearbox component that meshes with the rack gear
or a small gear on a starter motor that engages a
larger gear to rotate the engine flywheel.
PINION GEAR BEARING PRELOADDegree of
tightness of bearings, adjusted by compressing a
spacer or using shims.
PINION GEAR CLEARANCEDistance between
the pinion gear and drive end frame when the gear
PINION GEAR DEPTHThe distance the pinion
gear extends into the carrier to mesh with the ring
PINION PILOT BEARINGA bearing used to
support the pinion gear in the differential.
PINION SHAFTShaft holding the two differential
idler (pinion) gears.
PITCH LINEImaginary line along the center of a
PITMAN ARMComponent that transfers gearbox
motion to the steering linkage.
PITMAN SHAFT OVER-CENTER ADJUST-
MENTAdjustment of clearance between the
sector gear and the ball nut teeth in a recirculating
consisting of several
around a central "sun" gear.
PLUG GAPDistance between the center and side
electrodes on a spark plug.
PLUG HEAT RANGENumeric indicator of how
hot a spark the plug will develop.
PLUG REACHLength of the threaded portion of a
PLY SEPARATIONPulling apart of tire plies as a
result of overheating due to under inflation or other
POLE PIECEMagnetic component of a motor that
keeps the armature rotating.
POWER STEERING FLUIDA hydraulic oil,
usually automatic transmission fluid.
POWER STEERING PRESSURE TESTUse of a
pressure gauge to check pump and associated
components for correct pressure.
POWER STEERING PUMPUnit that provides
the hydraulic pressure needed in a power steering
components used. to transfer energy from the
engine to the wheels of the vehicle.
PRESSURE BLEEDINGA method of system
bleeding using additional pressure supplied by an
external air tank.
clamps the clutch disc against the flywheel.
PRESSURE PLATE COVERLid that bolts on the
pressure plate to hold various components in
PRESSURE PLATE FACEA large ring that
contacts the friction disc as the clutch engages.
PRESSURE PLATE RELEASE LEVERSLevers
hinged inside the pressure plate that help move the
pressure plate face away from the clutch disc and
PRIMARY AND SECONDARY SHOESFront
and back shoes in a drum brake system. The
secondary shoe has a larger surface area.
PRIMARY CIRCUITIn an ignition system, all
components are operating on battery (low)
PRIMARY WIRESmall insulated conductor that
carries battery or alternator voltage.
PROPORTIONING VALVEValve designed to
equalize pressure at the wheel cylinders on
vehicles with front disc and rear drum brakes.