how to resolve P0171 code in Honda Accord Eleventh Generation (2023-present)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety.
• Allow the engine to cool.

2. Inspect for Vacuum Leaks

• Visually inspect all vacuum hoses connected to the intake manifold.
• Use a smoke machine to detect any vacuum leaks if necessary.
• Tighten any loose connections or replace damaged hoses.

3. Clean or Replace MAF Sensor

• Remove the MAF sensor from the intake.
• Clean the sensor with MAF cleaner, avoiding contact with the sensing element.
• If cleaning does not yield results, replace the MAF sensor with a new unit.

4. Check Fuel Pressure

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position without starting the engine to check the fuel pressure.
  • It should be within the manufacturer’s specifications (typically around 40-50 psi for most Honda models).
• If pressure is low, inspect the fuel pump, fuel filter, and fuel lines for issues.

5. Inspect Oxygen Sensors

• Check the upstream (pre-catalytic converter) oxygen sensor for proper voltage readings (should fluctuate between 0.1 to 0.9 volts).
• Replace the sensor if it shows a steady reading or is outside the specified range.

6. Check and Clean Fuel Injectors

• If fuel injectors are suspected to be clogged, perform a fuel injector clean using a professional cleaning kit.
• Alternatively, replace any faulty injectors.