how to fix P0171 lean code on my Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

• Gather tools and materials.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool completely.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps, screwdriver.
• Instructions:
  1. Visually inspect all vacuum hoses for cracks or disconnections.
  2. Use a vacuum gauge to check for proper readings.
  3. Replace any damaged hoses and ensure all connections are tight.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, screwdriver.
• Instructions:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector and remove the sensor using the screwdriver.
  3. Clean the sensor with MAF sensor cleaner, allowing it to dry completely.
  4. Reinstall the sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Instructions:
  1. Locate the fuel rail and connect the fuel pressure gauge to the Schrader valve.
  2. Turn the ignition to the "On" position without starting the engine and check the pressure reading.
  3. Compare the reading to manufacturer specifications. If it is low, inspect the fuel pump and filter for issues.

5. Inspect Fuel Injectors

• Tools Required: Fuel injector cleaner, multimeter (for electrical testing).
• Instructions:
  1. Remove the fuel rail to access the injectors.
  2. Inspect the injectors for clogs or leaks.
  3. If needed, clean the injectors using a fuel injector cleaning kit or replace them if they are faulty.

6. Check Coolant Temperature Sensor

• Tools Required: Multimeter.
• Instructions:
  1. Locate the engine coolant temperature sensor.
  2. Disconnect the sensor and measure resistance with a multimeter.
  3. Compare readings to manufacturer specifications; replace if out of range.