how to fix P0171 code in Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down before starting work.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses connected to the intake manifold.
  • Use a smoke machine or carb cleaner to detect leaks.
  • Replace any damaged hoses or gaskets found during inspection.
• Tools Required: Vacuum gauge, smoke machine, or carb cleaner.

3. Check and Clean the MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the air intake duct.
  • Carefully remove the electrical connector and the sensor.
  • Clean the MAF sensor using MAF sensor cleaner; avoid touching the sensor element.
  • Reinstall the MAF sensor and reconnect the electrical connector.
• Tools Required: Screwdriver set, MAF sensor cleaner.

4. Inspect Fuel System Components

• Sub-steps:
  • Check the fuel pressure using a fuel pressure gauge; it should meet the manufacturer’s specifications.
  • If low, inspect the fuel pump and replace if necessary.
  • Inspect the fuel filter and replace it if it is clogged.
  • Check fuel injectors for proper operation; clean or replace as needed.
• Tools Required: Fuel pressure gauge, basic hand tools for fuel pump/filter removal.

5. Reset the ECM

• Sub-steps:
  • Reconnect the negative battery terminal.
  • Start the engine and allow it to reach operating temperature.
  • Monitor the engine parameters using an OBD-II scanner to check for codes.
• Tools Required: OBD-II scanner.