DTC 22 applies to both manual and auto vehicles. If you are still getting the code after trying three different TPS's (and I presume you mean new ones not used ones) then the problem could be in the wiring or maybe you have lost the small plastic piece in the throttle body when you replaced the TPS. Did you take the throttle body off to replace the TPS or did you try and replace it with the throttle body still in place? Some info on DTC 22 below:
DTC22 V8 ECM - THROTTLE POSITION (SIGNAL VOLTAGE LOW)
Circuit Description:
The Throttle Position (TP) sensor is attached to the throttle body, and is internally rotated by the throttle body shaft. It is a potentiometer with one end connected to 5 volts from the ECM and the other to ECM earth. A third wire is connected to the ECM, allowing it to measure the variable output voltage from the TP sensor.
As the throttle valve angle is changed (accelerator pedal moved), the TP sensor output voltage also changes in proportion. At a closed throttle position, the output voltage is usually below 1.25 volts as the throttle valve opens, the output increases so that at wide-open throttle, the output should be above 4.0 volts. By monitoring the output voltage from the TP sensor, the ECM can determine fuel needs based on throttle opening (driver demand).
A broken or loose TP sensor, or one that has an unstable output can cause intermittent bursts of fuel because the ECM thinks the throttle is moving. Results could include engine surge or poor idle quality. If the ECM interprets a high voltage when engine RPM is less than 400, hard starting could be the result (Clear-flood mode). A problem in any of the TP sensor circuits will set either a DTC 21 or DTC 22 after the engine is started. Once a DTC is set the ECM will use an artificial default value for TP sensor based on MAP and engine RPM to enable the vehicle to be driven, although performance could be less than normal.
The TP sensor is not adjustable. The ECM records the TP sensor voltage reading at idle and uses this as 0% throttle, so no adjustment is necessary.
DTC 22 will set if the TP sensor signal input voltage is less than about 0.2 volts for two seconds.