how to fix P0171 code in Toyota RAV4 XA50 (2019-2024)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface, and the engine is cool.
• Disconnect the negative battery terminal for safety.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:

  1. Visually inspect all vacuum hoses for cracks or disconnections.
  2. Use a smoke machine if available to identify vacuum leaks.
  3. Replace any damaged hoses or gaskets.

• Tools Required:

  • Smoke machine (optional)
  • Pliers
  • Replacement hoses/gaskets

3. Clean the MAF Sensor

• Sub-steps:

  1. Disconnect the MAF sensor electrical connector.
  2. Remove the MAF sensor from the air intake duct.
  3. Use MAF sensor cleaner to spray the sensing element and allow it to dry.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

• Tools Required:

  • MAF sensor cleaner
  • Screwdriver set

4. Check Fuel Pressure

• Sub-steps:

  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading; it should be within manufacturer specifications.
  3. If pressure is low, inspect the fuel pump and filter for issues and replace if necessary.

• Tools Required:

  • Fuel pressure gauge
  • Wrench set

5. Inspect and Clean the Throttle Body

• Sub-steps:

  1. Remove the air intake duct connected to the throttle body.
  2. Inspect the throttle body for carbon buildup.
  3. Clean the throttle body using throttle body cleaner and a soft cloth.
  4. Reinstall the air intake duct securely.

• Tools Required:

  • Throttle body cleaner
  • Soft cloth
  • Screwdriver set