how to fix P0171 code in Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shock.

Tools Required:

• OBD-II scanner
• Vacuum gauge
• Fuel pressure gauge
• Socket set
• Torque wrench
• Multimeter

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum lines and hoses connected to the intake manifold for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to identify leaks while the engine is running.
  3. Replace any damaged vacuum hoses.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Disconnect the electrical connector and remove the MAF sensor from the air intake duct.
  2. Clean the MAF sensor using a dedicated MAF sensor cleaner.
  3. Allow it to dry, then re-install the sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Sub-steps:
  1. Attach the fuel pressure gauge to the fuel rail service port.
  2. Turn the ignition to the "ON" position (do not start) and check the pressure reading against manufacturer specifications (usually around 50-60 psi).
  3. If pressure is low, check the fuel pump relay and fuse, and replace the fuel filter if necessary.

5. Inspect and Test Fuel Injectors

• Sub-steps:
  1. Remove the fuel injector connectors and use a multimeter to test for proper resistance.
  2. Check for any clogged injectors and clean or replace them as needed.
  3. Reconnect the injectors once repairs are complete.