how to fix P0171 code on Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down before starting work.

2. Inspect and Repair Air Intake System

• Sub-steps:
  • Remove the air intake duct to access the throttle body.
  • Check for any cracks or loose connections in the duct.
  • Inspect the air filter; replace it if dirty.
  • Reinstall the intake duct securely.

3. Clean or Replace MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the air intake path.
  • Disconnect the electrical connector from the MAF sensor.
  • Remove the MAF sensor using a Torx screwdriver.
  • Clean the sensor with MAF cleaner spray; do not touch the sensor element.
  • Reinstall the MAF sensor and reconnect the electrical connector.

4. Inspect Vacuum Lines

• Sub-steps:
  • Follow the vacuum lines from the intake manifold to the various components.
  • Look for any signs of wear, cracks, or disconnections.
  • Replace any damaged vacuum lines with new ones.

5. Test and Repair Fuel System

• Sub-steps:
  • Connect a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the ON position (engine off) to check the fuel pressure.
  • Compare the reading with the manufacturer’s specifications (typically around 40-50 psi).
  • If the pressure is low, inspect the fuel pump and fuel filter for issues.
  • Replace the fuel filter if necessary.

6. Check Fuel Injectors

• Sub-steps:
  • Remove the fuel injector rail to access the injectors.
  • Inspect the injectors for dirt or clogs; clean them if needed.
  • Test the injectors using a multimeter to ensure they are within specifications.
  • Replace any faulty injectors.