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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety.
• Allow the engine to cool down if it has been running.

2. Inspect and Repair Vacuum Leaks

• Check all vacuum lines and hoses for cracks or disconnections.
• If any leaks are found, replace the damaged hoses with OEM replacement parts.
• Use a smoke machine if available to identify hard-to-find leaks.

3. Clean or Replace the MAF Sensor

• Remove the MAF sensor from the air intake.
• Use MAF sensor cleaner to spray the sensing element. Allow it to dry completely.
• Reinstall the MAF sensor, ensuring it is securely connected.

4. Check Fuel System

• Connect a fuel pressure gauge to the fuel rail.
• Start the engine and check the fuel pressure against manufacturer specifications (typically around 30-40 psi for most systems).
• If pressure is low, check the fuel pump and filter for proper operation. Replace any failing components.

5. Inspect Fuel Injectors

• Remove the fuel injectors and inspect for clogs or leaks.
• Clean the injectors using an ultrasonic cleaner if they're dirty, or replace them if they are leaking.

6. Reassemble and Reconnect

• Reassemble any removed components in reverse order.
• Reconnect the battery.
• Clear the error codes using the OBD-II scanner.