What is P1171?
P1171 code, (17579/P1171/004465) often indicates problems with Angle Sensor 2 (G188) of the Throttles Actuator in VW vehicles. The very definition explains an implausible signal, which means the ECM receives data from the sensor that does not conform to expected values.
The primary function of this sensor is to send a signal for the regulation of the throttle body, which, in turn, controls the airflow into the engine. Should it fail, performance issues on the engine can arise.
Possible Symptoms of P1171
The P1171 stored fault code would mean some symptoms would likely be noticed by the driver:
Check engine light (MIL) illuminated
Engine hesitation or poor throttle response
Erratic or unstable idling
Engine stalling
Reduced power or limp mode activation
The Causes of the P1171 Code
The main causes of the P1171 error include:
Faulty Angle Sensors (G187/G188)
If Angle Sensor 2 (G188) fails or sends an incorrect signal, a possible trigger of this code is present.
Throttle Actuator Dysfunction
Throttle Actuator is responsible for the air passage and a failing actuator could mislead the sensors.
Wiring or Connector Problems
Corroded, loose, or damaged wires connecting the throttle actuator sensors to the ECU will cause disruption to the signals.
ECM Power Supply Issue
If for some reason the ECM isn’t properly supplied with voltage, it would naturally be expected to misinterpret the sensor information.
Dirty/Sticky Throttle: Carbon may build up and prevent proper movement and affect the throttle position sensors.
How Do I Fix the P1171 Codes for My Volkswagen?
Below are diagnostic procedures and solutions that should be taken into consideration:
1. Inspect the Throttle Angle Sensors (G187/G188)
Check live data from these sensors using an OBD-II scanner.
Abnormal readings in the Measuring Value Blocks (MVB), usually MVB 062, are the main indicators used.
2. Throttle Body Inspection and Cleaning
After removal, the cleaned throttle body with throttle body cleaner should remove any carbon deposits.
Confirm that the throttle plate is free to move.
3. Inspect Wiring and Connectors
Check the harness and connectors between the throttle body and the ECU for corrosion, damage, or loose connections.
Repair or replace any faulty wiring.
4. Check the Throttle Actuator
Replace if found defective.
When installing the actuator, perform a throttle body adaptation using a tool like VCDS (VAG-COM).
5. Reset the ECM and Perform a Throttle Body Adaptation
Clear the P1171 code using an OBD-II scanner.
Throttle adaptation can be performed using VCDS or similar software.
– Switch the ignition ON (without starting the engine).
– Wait 30 to 60 seconds for the ECU to recalibrate the throttle.
– Turn off the ignition for 10 seconds, and restart the engine.
Is It Okay to Drive with the P1171 Code?
Driving with P1171 is not advisable. Your car may go to limp mode, with reduced power so that it does not damage itself. An untreated code may result in poor performance, increased fuel consumption, or even the throttle being completely unresponsive.
In Conclusion
For one, if P1171 VW code comes up, it would be ideal to clean out the throttle body and check the wiring. If this does not remedy the problem, one might have to get an angle sensor or throttle actuator. Further diagnosis with VCDS or an OBD-II scanner will help track down the exact cause.
Would you need assistance with a specific VW model that is having this issue?
