how to fix the P0171 code in my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, fuel pressure gauge, cleaning supplies (e.g., MAF cleaner).
• Allow the engine to cool before starting any work.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Repair Air Intake System

1. Visually inspect the air intake hoses and connections for cracks or disconnections.
2. Tighten or replace any loose or damaged hoses.
3. If cracks are found, replace the affected parts with OEM equivalents.

3. Clean or Replace MAF Sensor

1. Locate the MAF sensor (typically situated between the air filter and throttle body).
2. Remove the sensor using a socket set, taking care not to damage the electrical connector.
3. Clean the MAF sensor using MAF cleaner spray. Allow it to dry before reinstallation.
4. If the sensor is damaged, replace it with a new one.

4. Check Fuel Pressure

1. Connect a fuel pressure gauge to the fuel rail test port.
2. Turn the ignition to the "ON" position (without starting the engine) and observe the fuel pressure reading.
3. Compare the reading to the manufacturer's specifications (typically found in the service manual).
4. Replace the fuel pump or filter if the pressure is below specifications.

5. Inspect Fuel Injectors

1. Remove the engine cover if required to access the injectors.
2. Visually inspect the injectors for signs of leaks or damage.
3. Use a multimeter to check the resistance of the injectors; replace if out of specification.
4. If clogged, clean the injectors using a professional-grade fuel injector cleaner.

6. Check for Exhaust Leaks

1. Inspect the exhaust manifold and pipes for visible signs of leaks.
2. Use a smoke test or soapy water to find any hidden leaks.
3. Repair or replace any leaking exhaust components.