Reduced Engine Power - PO1125

I have a 04 GTP with 106K miles. At 87K I had to replace the motor due to a bottom end problem and have 66K on the new motor. The new motor came online fine with no issues and has performed well. Recently, if I get on her, passing, merging, etc. I get the DING DING and "Reduced Engine Power". Throws a PO1125 code. I can shut it down, wait a minute or two and it starts right up and the check light goes out. The car runs fine (other than bad gas mileage that I haven 't figured out yet), and no other codes or problems. I can even accelerate fairly quickly without any problems. Only when I ROMP on it, it dies at about 3200 RPM.

I suspect its a throttle pos sensor or someting, but its going to take someone better than me to tell me how to test, fix this. Many thanks in advance for your help on this one.
What's the point of having a GTP if it croaks at 3200 RPMs?

P01125?

Sounds like an issue with the accel. pedal position sensor. Part of the pedal assembly.

The control module provides the APP sensors a 5-volt reference circuit and a low reference circuit. The APP sensors then provide the control module signal voltages proportional to pedal movement. The APP sensor 1 signal voltage is low at rest and increases as the pedal is depressed. The APP sensor 2 signal voltage is also low at rest and increases as the pedal is depressed. One APP sensor DTC will not cause the Reduced Engine Power message to be displayed. Two APP sensor DTCs for the same sensor also will not cause the Reduced Engine Power message to be displayed. However, if two or more DTCs are set involving more than one APP sensor, DTC P1125 will set.

The accelerator pedal position (APP) sensor 1 and APP sensor 2 are potentiometer type sensors, each with the following circuits:A 5-volt reference circuit A low reference circuit A signal circuit

Conditions for Running the DTCDTCs P0606, P1518, P2108 are not set. The ignition is ON. The communications between the throttle actuator control (TAC) module and the powertrain control module (PCM) must be valid. Conditions for Setting the DTCTwo APP sensors are out of range or both APP sensors disagree with each other.Action Taken When the DTC SetsThe control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records. The control module commands the TAC system to operate in the Reduced Engine Power mode. A message center or an indicator displays Reduced Engine Power. Under certain conditions the control module commands the engine

thats off of shopkey5 under code p1125