my Toyota Camry Eighth Generation (2018-present) has a check engine light with code P0171

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdriver set, vacuum gauge
• Inspect all hoses and connections for cracks or loose fittings.
  • Tighten any loose clamps.
  • Replace any damaged vacuum hoses.
• If a leak is found, seal it using appropriate hose clamps or replace the affected component.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, screwdriver set
• Remove the MAF sensor from the air intake duct.
• Spray the sensor with MAF cleaner and allow it to dry completely before reinstalling.
• If the sensor is damaged, replace it with a new one.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge
• Attach the fuel pressure gauge to the fuel rail service port.
• Turn the ignition key to the "ON" position (do not start) and check the fuel pressure reading.
  • Compare the reading with the manufacturer’s specifications.
  • If the pressure is low, inspect the fuel pump and filter for issues.

5. Inspect and Clean Fuel Injectors

• Tools Required: Injector cleaning kit, socket set
• Remove the fuel injector rail to access the injectors.
• Use the injector cleaning kit to flush out contaminants or replace the injectors if they are malfunctioning.
• Reinstall the injector rail, ensuring all connections are secure.