how to resolve P0171 code on Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool before starting work.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify leaks while the engine is running.
  • Replace any damaged hoses or gaskets.

3. Check and Clean Mass Airflow Sensor (MAF)

• Sub-steps:
  • Locate the MAF sensor in the intake duct.
  • Disconnect the electrical connector and remove the sensor.
  • Use MAF cleaner to clean the sensor wires delicately.
  • Reinstall the MAF sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Sub-steps:
  • Attach a fuel pressure gauge to the fuel rail.
  • Turn the ignition to the "ON" position without starting the engine to check the pressure.
  • Compare the reading to the manufacturer's specifications (typically between 40-50 psi).
  • If pressure is low, inspect the fuel pump and replace if necessary.

5. Inspect Fuel Injectors

• Sub-steps:
  • Remove the engine cover for access to the fuel injectors.
  • Use a multimeter to test the resistance of each injector.
  • Clean or replace any faulty injectors.