What Does P1171 Mean?
This code indicates the second throttle actuation potentiometer (throttle position sensor 2) is showing a signal that is outside its expected range or is not correlating properly with the primary TPS signal. In electronic throttle control (drive-by-wire) systems, two potentiometers provide redundant throttle position feedback. When the second signal deviates from its expected relationship with the first, this range/performance fault is set, potentially causing the PCM to limit throttle authority.
Safety Warning
The PCM may enter reduced power (limp) mode, limiting vehicle speed and throttle response. This can be hazardous when full power is needed for highway merging, passing, or emergency maneuvers. Immediate diagnosis and repair is recommended.
Common Causes
30%
Worn or contaminated throttle position potentiometer 2 (carbon track wear)
25%
Intermittent connection at the throttle body connector affecting TPS 2 signal
20%
Throttle body contamination (carbon buildup) causing mechanical binding that affects TPS 2 tracking
15%
Wiring issue (high resistance or slight short) in the TPS 2 circuit
10%
Faulty throttle body assembly requiring complete replacement
Diagnostic Steps
1
Monitor both TPS 1 and TPS 2 voltages simultaneously in live data while slowly sweeping the throttle from closed to wide-open; the signals should mirror each other (one typically increasing, one decreasing) smoothly without flat spots or dropouts.
2
Graph the TPS 2 signal and look for dead spots, voltage spikes, or areas where the signal flatlines; these indicate worn potentiometer tracks.
3
Inspect the throttle body connector for corrosion, bent pins, or loose terminals; clean and reseat the connector.
4
Clean the throttle body bore and plate using appropriate throttle body cleaner; carbon buildup can cause binding that affects position tracking.
5
If the potentiometer has confirmed dead spots or erratic output, replace the throttle body assembly (TPS is typically not serviceable separately on electronic throttle systems).
Estimated Repair Cost
$200 - $700
Parts + labor, varies by vehicle and location
This code indicates the second throttle actuation potentiometer (throttle position sensor 2) is showing a signal that is outside its expected range or is not correlating properly with the primary TPS signal. In electronic throttle control (drive-by-wire) systems, two potentiometers provide redundant...
The most common cause of P1171 (Throttle Actuation Potentiometer Sign. 2 Range/Performance) is: Worn or contaminated throttle position potentiometer 2 (carbon track wear)
Typical repair costs for P1171 range from $200 to $700, depending on the vehicle, location, and whether you do it yourself or go to a shop.
The PCM may enter reduced power (limp) mode, limiting vehicle speed and throttle response. This can be hazardous when full power is needed for highway merging, passing, or emergency maneuvers. Immediate diagnosis and repair is recommended.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1171 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Electronic Throttle Control
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
