how to resolve P0171 code on Honda Civic 11th Generation (2022-Present)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to identify leaks by spraying it around suspected areas while the engine is running.
  3. Replace any damaged hoses or seals found during inspection.

3. Clean the MAF Sensor

• Tools Required: MAF sensor cleaner or electrical cleaner
• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector from the MAF sensor.
  3. Remove the MAF sensor from the intake duct.
  4. Spray the sensor with MAF cleaner and let it dry completely.
  5. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge
• Sub-steps:
  1. Locate the fuel rail test port.
  2. Connect the fuel pressure gauge to the test port.
  3. Turn the ignition on (do not start the engine) to check the fuel pressure reading.
  4. If pressure is below specifications, inspect the fuel pump and filter.
  5. Replace the fuel filter if clogged and consider replacing the fuel pump if it fails to deliver the correct pressure.

5. Verify ECT Sensor

• Sub-steps:
  1. Use a multimeter to test the ECT sensor's resistance.
  2. Compare readings to specifications in the service manual.
  3. Replace the ECT sensor if the readings are out of range.