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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before starting any work.

2. Inspect Air Intake System

• Tools Required: Screwdriver set, flashlight
• Inspect the air intake duct for cracks or loose fittings.
• If any damage is found, replace the damaged components or secure any loose connections.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, Torx screwdriver
• Remove the MAF sensor from the air intake.
• Spray the MAF sensor with MAF cleaner and allow it to dry completely.
• Reinstall the MAF sensor securely.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge, adapter fittings
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition to the “ON” position (do not start the engine) to check the pressure.
• Compare the reading to the manufacturer’s specifications. If it is low, check the fuel pump and filter.

5. Inspect Fuel Injectors

• Tools Required: Fuel injector cleaner, multimeter
• Visually inspect the fuel injectors for signs of leaks or blockage.
• If necessary, use fuel injector cleaner to clean the injectors or replace them if they are faulty.

6. Check Vacuum Hoses

• Tools Required: Visual inspection tools
• Inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
• Replace any damaged hoses.