how to fix the P0171 code on my Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical issues.
• Allow the engine to cool down before proceeding with repairs.

2. Inspect the Air Intake System

• Tools Required: Screwdriver set, vacuum gauge.
• Inspect all components of the air intake system for cracks or loose fittings.
• Use a vacuum gauge to check for any excessive leaks; repair or replace any damaged hoses.

3. Clean or Replace the MAF Sensor

• Tools Required: MAF sensor cleaner (non-residue type).
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with a dedicated cleaner and allow it to dry completely before reinstallation.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Locate the fuel rail test port, and connect the gauge.
• Turn the ignition to the "On" position (do not start the engine) to check the fuel pressure; it should meet the manufacturer specifications (usually around 40-50 psi). Replace the fuel pump or filter if readings are low.

5. Inspect Fuel Injectors

• Tools Required: Multimeter, fuel injector cleaning kit (if necessary).
• Check the electrical connections to each injector with a multimeter for continuity.
• Use a fuel injector cleaning kit to clean the injectors if they appear clogged.

6. Verify Engine Coolant Temperature Sensor

• Tools Required: Multimeter.
• Disconnect the ECT sensor and measure its resistance at various temperatures to ensure it operates within specifications.
• Replace the ECT sensor if it fails the resistance test.