how to fix Honda Accord 10th Generation (2018-2022) P0171 code for lean mixture

Solution

1. Preparation

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

2. Inspect for Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses and connections for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify leaks while the engine is running.
• Tools Required:
  • Smoke machine or carburetor cleaner
• Safety Warnings:
  • Ensure the engine is cool before inspecting hoses.

3. Test Fuel Pressure

• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
  • Compare the reading to the manufacturer specifications (typically between 40-50 psi).
  • If pressure is low, inspect the fuel pump and filter.
• Tools Required:
  • Fuel pressure gauge

4. Clean or Replace MAF Sensor

• Sub-steps:
  • Disconnect the electrical connector from the MAF sensor.
  • Remove the sensor from the air intake duct.
  • Clean the MAF sensor with MAF cleaner spray, ensuring not to touch the sensor element.
  • Reinstall the sensor and reconnect the electrical connector.
• Tools Required:
  • MAF cleaner spray
  • Screwdriver set

5. Inspect Fuel Injectors

• Sub-steps:
  • Remove the intake manifold if necessary to access the fuel rail and injectors.
  • Visually examine the injectors for leaks or clogs.
  • Use a multimeter to check the resistance of each injector (should typically be around 12-16 ohms).
  • Replace any faulty injectors.
• Tools Required:
  • Multimeter
  • Socket set

6. Replace Oxygen Sensors (if necessary)

• Sub-steps:
  • If the oxygen sensors are determined to be faulty, disconnect the battery.
  • Remove the old oxygen sensor using an oxygen sensor socket.
  • Install the new sensor and reconnect the electrical connector.
  • Reconnect the battery.
• Tools Required:
  • Oxygen sensor socket
  • Wrench set