how to fix P0171 code on Toyota Corolla E140 (2006-2013)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Inspect and Repair Air Intake System

• Sub-steps:

  1. Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  2. Tighten any loose clamps and replace any damaged hoses.
  3. Check the intake manifold gasket for leaks and replace if necessary.

• Tools Required:

  • Socket set
  • Pliers

3. Clean or Replace MAF Sensor

• Sub-steps:

  1. Disconnect the MAF sensor electrical connector.
  2. Remove the MAF sensor from the air intake duct.
  3. Clean the MAF sensor with MAF cleaner spray, allowing it to dry completely.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

• Tools Required:

  • Screwdriver set
  • MAF cleaner spray

4. Verify Fuel System

• Sub-steps:

  1. Connect a fuel pressure gauge to the fuel rail service port.
  2. Turn the ignition to the "ON" position without starting the engine to check the fuel pressure.
  3. If the pressure is below specifications, replace the fuel filter and inspect the fuel pump for proper operation.

• Tools Required:

  • Fuel pressure gauge
  • Wrench set

5. Inspect and Clean Fuel Injectors

• Sub-steps:

  1. Remove the fuel rail assembly to access the injectors.
  2. Inspect each injector for clogs and leaks.
  3. Use an injector cleaning kit to clean the injectors or replace them if necessary.

• Tools Required:

  • Injector cleaning kit
  • Torque wrench (for reassembly)