how to fix P0171 lean code in Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, fuel pressure gauge, multimeter, socket set, cleaning solvent, shop towels.
• Safety Warnings: Disconnect the battery before working on electrical systems. Allow the engine to cool before starting work.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Visually inspect the air filter for dirt and replace it if dirty.
  2. Check the air intake hose for cracks or loose fittings and replace as necessary.
  3. Tighten any loose clamps or connections in the air intake system.

3. Check and Clean MAF Sensor

• Sub-steps:
  1. Disconnect the electrical connector from the MAF sensor.
  2. Remove the MAF sensor from its housing using the appropriate socket.
  3. Clean the MAF sensor element with MAF cleaner spray and let it dry completely.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Test and Adjust Fuel System

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the "ON" position without starting the engine and check the fuel pressure reading.
  3. If the pressure is below specifications, inspect the fuel pump, fuel filter, and fuel lines for issues.
  4. Replace any faulty components and check that the fuel pressure is within the proper range.

5. Inspect and Service Fuel Injectors

• Sub-steps:
  1. Disconnect the fuel injector connectors.
  2. Remove the fuel rail with the injectors attached.
  3. Inspect each injector for clogs or leaks; clean with appropriate injector cleaner if needed.
  4. Reinstall the fuel rail and reconnect the fuel injector connectors.