how to fix P0171 lean code in Honda Accord Eleventh Generation (2023-present)

Solution

1. Preparation

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

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdriver, vacuum gauge.
• Steps:
  1. Remove the air intake duct and inspect for cracks or loose fittings.
  2. Tighten any loose clamps and replace damaged hoses or gaskets.

3. Fuel System Inspection

• Tools Required: Fuel pressure gauge.
• Steps:
  1. Connect the fuel pressure gauge to the fuel rail according to the manufacturer's specifications.
  2. Turn the ignition to the "ON" position (do not start) and check the pressure reading; it should match the specifications in the service manual.
  3. If pressure is low, inspect the fuel pump, filter, and fuel injectors for blockage or failure.

4. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner.
• Steps:
  1. Disconnect the wiring harness and remove the MAF sensor from the intake.
  2. Spray the MAF sensor with MAF cleaner and allow it to dry completely before reinstalling.
  3. Reattach the sensor and wiring harness.

5. Inspect and Repair Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner.
• Steps:
  1. Use a smoke machine to introduce smoke into the intake system; watch for smoke escaping, indicating a leak.
  2. If using carburetor cleaner, spray around suspected areas while the engine is running and listen for RPM changes.
  3. Repair any identified leaks by replacing gaskets or hoses.

6. Oxygen Sensor Check

• Tools Required: Multimeter.
• Steps:
  1. Locate the upstream oxygen sensor and disconnect the wiring harness.
  2. Use a multimeter to check the sensor's resistance and voltage output according to specifications.
  3. Replace the sensor if it is malfunctioning.