Transmission Definitions

THROTTLE POSITIONS
Minimum Throttle: The least amount of throttle opening required for upshift.
Light Throttle: Approximately 1/4 of the accelerator pedal.
Medium Throttle: Approximately 1/2 of the accelerator pedal travel.
Heavy Throttle: Approximately 3/4 of the accelerator pedal travel.
Wide Open Throttle (WOT): Full travel of the accelerator pedal.
Full Throttle Detent Densified: A quick application of the accelerator pedal to its full travel in order to force a downshift.
Engine Braking: A condition in which you use the engine in order to slow the car by downshifting manually during a zero-throttle coastdown.
Zero Throttle Coastdown: A full release of the accelerator pedal while the car is in motion and in drive range.

SHIFT CONDITIONS
Bump: A sudden and forceful engagement of a clutch or band.
Chuggle: A bucking or jerking that is most noticeable when the converter clutch is engaged. A Chuggle is similar to the feel of towing a trailer.
Delayed: A condition in which a shift is expected but does not occur for a period of time. Delayed is also defined as late or Extended.
Double Bump (Double Feel): Two sudden and forceful engagements of a clutch or a band.
Early: A condition in which the shift occurs before the car has reached the proper speed. The early condition tends to labor the engine after the upshift.
End Bump: A firmer feel at the end of a shift as compared to the feel at the start of the shift. End bump also is define as END FEEL or SLIP BUMP.
Firm: A noticeably quick engagement of a clutch or band that is considered normal with a medium to heavy throttle. This should not be confused with HARSH or ROUGH.
Flare: A quick increase in engine rpm along with a momentary loss of torque. This generally occurs during a shift. Flare is also defined as SLIPPING.
Harsh (Rough): A more noticeable engagement of a clutch or a band as compared with FIRM. This condition is considered undesirable at any throttle position.
Hunting: A repeating quick series of upshifts and downshifts that causes a noticeable change in engine rpm. An example is a 4-3-4 shift pattern. Hunting also is defined as BUSYNESS.
Initial Feel: A distinct sturdy feel at the start of a shift as compared to the end of the shift.
Late: A shift occurs when the engine is at a higher than normal rpm for a given amount of throttle.
Shudder: A continuous jerking condition similar to CHUGGLE but more severe and rapid. This condition is most noticeable during certain car speed ranges.
Slipping: A noticeable increase in engine rpm without a car speed increase. A slip usually occurs during or after the initial clutch or band engagement.
Soft: A slow, almost unnoticeable clutch or band engagement with very little shift feel.
Surge: A repeating acceleration and deceleration that is engine-related. This condition is less intense than CHUGGLE.
Tie Up: A condition in which two opposing clutches and/or bands are attempting to engage at the same time, causing the engine to labor with a noticeable loss of engine rpm.

NOISE CONDITIONS
Planetary Gear Noise: A whine related to the car speed that is most noticeable in the first gear or reverse. Planetary Gear Noise is less noticeable after an upshift.
Pump Noise: A high pitch whine that increases with engine rpm.

ABBREVIATIONS
^ PCM-Powertrain Control Module
^ TCC-Torque Converter Clutch
^ TP Sensor-Throttle Position Sensor
^ ECT Sensor-Engine Coolant Temperature Sensor
^ VSS Sensor-Vehicle Speed Sensor
^ RWD-Rear Wheel Drive
^ 2WD-2 Wheel Drive
^ 4WD-4 Wheel Drive
^ TFP Manual Valve Position Switch-Automatic Transmission Fluid Pressure Manual Valve Position Switch
^ TFT Sensor-Automatic Transmission Fluid Temperature Sensor