Problem: This vehicle came to the shop for hesitation and poor acceleration. The technician found DTC P2138 – Throttle Position Sensor D/E Incorrect Voltage Correlation.
Details: Acura uses a throttle cable from the pedal to the APP (Accelerator Pedal Position) sensor, which in turn sends the position signal to the ETC (electronic throttle control) system and adjusts the throttle angle according to the APP sensor output.
Hint: First, double check the adjustment of the throttle cable free play and adjust as necessary.
Back-probe terminals 3 and 4 with a “T” pin.
Ignition ON, engine OFF.
Measure the voltages as shown in the diagram.
If results are NOT as expected, replace the APP sensor.
If results are as expected, check the wiring and connectors for looseness or damage and remedy as necessary
Confirmed Repair: In this case, the APP voltage tests were within specifications so the technician replaced the APP sensor. He adjusted the throttle cable to specifications and cleared the DTC. There was no need for reprogramming. A quick test drive confirmed the problem was repaired.