how to fix P0171 code in Toyota Corolla E170 (2013-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during repairs.
• Allow the engine to cool down before starting work.

2. Inspect Air Intake System

• Sub-steps:
  1. Visually inspect the air intake duct for cracks or loose connections.
  2. Tighten or replace any loose or damaged sections.
• Tools Required: Screwdriver set, flashlight

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Remove the MAF sensor from the air intake.
  2. Use MAF cleaner to gently clean the sensor elements.
  3. Reinstall the sensor ensuring a secure fit.
• Tools Required: Torx screwdriver, MAF cleaner spray

4. Test and Repair Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition key to the "ON" position to check the fuel pressure.
  3. If pressure is low, inspect the fuel pump and filter and replace if necessary.
• Tools Required: Fuel pressure gauge, socket set

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. Remove the injectors from the fuel rail.
  2. Use a fuel injector cleaning kit to clean the injectors thoroughly.
  3. Reinstall the injectors and ensure they are seated properly.
• Tools Required: Injector cleaning kit, socket set

6. Replace Oxygen Sensor (if necessary)

• Sub-steps:
  1. Locate the upstream oxygen sensor and disconnect the electrical connector.
  2. Use an oxygen sensor socket to remove the sensor from the exhaust manifold.
  3. Install the new oxygen sensor and reconnect the electrical connector.
• Tools Required: Oxygen sensor socket, wrench set