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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect all hoses connected to the air intake for cracks or damage.
  2. Use a vacuum pump to check for leaks in the intake manifold gaskets.
  3. Replace any damaged hoses or gaskets found during inspection.

3. Clean or Replace Mass Airflow Sensor (MAF)

• Sub-steps:
  1. Remove the MAF sensor from the air intake duct.
  2. Use MAF sensor cleaner to clean the sensor elements gently.
  3. If cleaning does not resolve the issue, replace the MAF sensor with a new one.

4. Test and Repair Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Start the engine and monitor fuel pressure; it should meet the manufacturer's specifications (typically around 40-50 psi).
  3. If the pressure is low, inspect the fuel pump, fuel filter, and fuel injectors.
  4. Replace the fuel filter if clogged and ensure the fuel pump is functioning correctly.

5. Check and Repair Vacuum Leaks

• Sub-steps:
  1. Inspect all vacuum lines connected to the intake manifold for cracks.
  2. Replace any damaged vacuum lines.
  3. Use a smoke machine to detect hard-to-find vacuum leaks if necessary.