how to fix the P0171 lean code on my Toyota RAV4 XA50 (2019-2024)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Repair Vacuum Leaks

• Inspect Vacuum Hoses: Visually check all vacuum hoses for cracks or disconnections.
• Use Smoke Test (if necessary): Introduce smoke into the intake system to identify leaks.
• Repair or Replace: Replace any damaged hoses or seals.

3. Inspect and Clean MAF Sensor

• Remove MAF Sensor: Disconnect the MAF sensor connector and remove the sensor from the intake.
• Clean Sensor: Use MAF sensor cleaner to gently clean the sensing elements. Allow it to dry completely.
• Reinstall MAF Sensor: Reattach the MAF sensor and connector securely.

4. Fuel System Inspection

• Check Fuel Filter: Inspect the fuel filter and replace it if it is clogged or dirty.
• Test Fuel Pressure: Connect a fuel pressure gauge to the fuel rail. Ensure the pressure meets manufacturer specifications (typically around 50-60 psi for RAV4).
• Replace Fuel Pump (if necessary): If fuel pressure is low, consider replacing the fuel pump.

5. Reset Engine Control Module (ECM)

• Reconnect the battery.
• Start the engine and allow it to reach operating temperature.
• Use the OBD-II scanner to clear the P0171 code from the ECM.