how to fix P0171 code on Honda Civic 11th Generation (2022-Present)

Solution

1. Preparation

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

2. Inspect for Vacuum Leaks

• Tools Required: Vacuum gauge, smoke machine (optional).
• Visually inspect all vacuum lines connected to the intake manifold for cracks or disconnections.
• Use a smoke machine or a vacuum gauge to detect any hidden vacuum leaks around the intake manifold and hoses.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, Torx or Phillips screwdriver.
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with MAF sensor cleaner and allow it to dry completely before reinstalling.
• Reattach the MAF sensor ensuring a secure connection.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Connect the fuel pressure gauge to the fuel rail test port.
• Start the engine and observe the pressure; it should be within the manufacturer’s specifications (usually 30-50 psi for most Honda models).
• If pressure is low, inspect the fuel pump and filter for issues.

5. Inspect and Test Fuel Injectors

• Tools Required: Multimeter, injector cleaning kit (if necessary).
• Disconnect the fuel injector connectors and check for voltage using a multimeter while the engine is cranking.
• If voltage is present and injectors are not firing, consider cleaning or replacing the injectors.

6. Check Oxygen Sensors

• Tools Required: OBD-II scanner.
• Use the OBD-II scanner to monitor live data from the oxygen sensors.
• If the upstream oxygen sensor readings are not fluctuating or responding correctly, consider replacing the sensor.