Powertrain, generic (extended)

P2166 Throttle/Pedal Position Sensor D Maximum Stop Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2166 refers to position signal D, which on Ford designs is the first track of the accelerator pedal. The code means the reading with the pedal pressed all the way does not match the calibrated maximum, for instance because the pedal never reaches its stop or the track is worn at the far end. No manufacturer documents P2166 publicly; it applies the logic of the A version P2163 and of the open-stop learning in a Visteon patent to the pedal. A thick floor mat, a bent pedal arm or a worn pedal module are typical causes. The engine computer may then cap the torque request, so the car feels as if it never reaches full power. P2115 covers the rest position of D, P2120-P2124 its circuit, and P2138 the D/E correlation.

Likely causes

Floor mat or object keeps the pedal from its stop
Pedal sensor track D worn at full travel
Bent pedal arm or damaged pedal bracket
Corroded pedal connector shifting signal D

Symptoms

  • Engine warning lamp on
  • No kickdown or no full power with the pedal floored
  • Possible limp mode

Repair estimate

DifficultyEasyDIY possible
Parts and labour€0–350
Time0.2–1 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

accelerator pedal position sensorthrottle position sensor

Related codes

P2115P2167P2122P2138

References: patents.google.com, newtonnet.co.uk, law.cornell.edu.