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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative terminal of the battery to prevent electrical shorts.
• Gather safety gear such as gloves and safety glasses.

2. Inspect and Repair Air Leaks

• Step 1: Visually examine all vacuum hoses for cracks or disconnections. Replace any damaged hoses.
• Step 2: Use a smoke machine or carburetor cleaner to identify any leaks in the intake system.
• Step 3: Tighten any loose clamps around the air intake and throttle body.

3. Clean or Replace MAF Sensor

• Step 1: Disconnect the MAF sensor connector.
• Step 2: Remove the MAF sensor from the air intake duct using a Torx or Phillips screwdriver.
• Step 3: Clean the MAF sensor with MAF sensor cleaner; do not use any other type of cleaner.
• Step 4: Allow the sensor to dry, then reinstall it securely.

4. Check Fuel System Pressure

• Step 1: Connect a fuel pressure gauge to the fuel rail.
• Step 2: Turn the ignition on (do not start the engine) and record the fuel pressure reading.
• Step 3: Compare it to the manufacturer’s specifications (typically 30-40 psi). If it’s low, check the fuel pump and filter.
• Step 4: Replace the fuel filter if clogged and the fuel pump if it fails to deliver proper pressure.

5. Inspect Fuel Injectors

• Step 1: Remove the fuel rail with the injectors attached.
• Step 2: Inspect the injectors for clogs or leaks; clean or replace as necessary.
• Step 3: Reinstall the fuel rail, ensuring proper connections.

6. Reset the ECM

• Step 1: Reconnect the negative battery terminal.
• Step 2: Use an OBD-II scanner to clear the P0171 code.
• Step 3: Start the engine and allow it to idle for several minutes.