P2166: Throttle/Pedal Position Sensor D Maximum Stop Performance
What to do
Check under the pedal for an obstruction before anything else — it is free and it genuinely causes this. If codes are also stored for sensors in the other group, the problem is more likely the pedal or throttle travel itself than any one sensor.
What this code means
The learned fully open position for sensor D has drifted. The argument is under P2164.
Sensor D opens the second group of position sensors — the group whose circuit codes run P2120 to P2124 and whose correlation codes are P2138 and P2139. Grouping matters here for the same reason it does everywhere in this range: a fault confined to one group implicates that group's own sensors and wiring, while a fault crossing both groups implicates the thing they share, which is the physical travel being measured.
Likely causes
Start here
Less common
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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