Range: 0 to 100%
The position of the Throttle Position Sensor (TPS) on the throttle body. The % should directly corrolate to the gas pedal position. This is an absolute value based on a 0 to 5 volt sensor output. Meaning on 99% of cars out there, the value will never reach 0 or 100% because the throttle will hit mechanical stops before reaching the full travel of the sensor.
The ECU typically uses the TPS to sense changes in throttle, not a particular throttle position. When the ECU senses a positive change in throttle position, extra fuel is injected, much like the accelerator pump on carburetors. it may use a TPS
If the signal jumps around (usually happens at a single throttle position, but can happen at any time) then you could have a bad TPS sensor. This would cause bucking or hesitation while driving.
The Apex-i S-AFC uses the minimum and maximum TPS voltage it sees as 0% and 100% so the number displayed on the AFC will not match the TPS value on the PocketLOGGER.
'00 Toyota MR2 SPYDER
Greddy E-manage also uses 0-100% TPS corresponding to 12% and 80% on the OBDII port.