how to fix P0171 code in Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

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

2. Clean MAF Sensor

• Tools Required: MAF sensor cleaner
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with MAF cleaner and allow it to dry completely.
• Reinstall the MAF sensor and reconnect any electrical connectors.

3. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps
• Visually inspect all vacuum hoses for cracks, splits, or loose connections.
• Use a vacuum gauge to test the intake manifold for leaks.
• Replace any damaged hoses or tighten loose connections.

4. Check and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel rail and connect the fuel pressure gauge.
• Turn the ignition to the "ON" position (do not start the engine) and check the reading.
• If the pressure is below specifications (typically around 50-60 PSI), inspect the fuel pump and filter for issues and replace as necessary.

5. Inspect Fuel Injectors

• Tools Required: Injector cleaner, multimeter
• Remove the fuel rail to access the injectors.
• Inspect for clogs, and if necessary, use injector cleaner to clean them.
• Use a multimeter to check the resistance of each injector. Replace any that are out of specification (typically around 12-16 ohms).