how to fix P0171 code Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to prevent electrical shocks.

Tools Required:

• OBD-II scanner
• Vacuum gauge
• Fuel pressure gauge
• Socket set
• Torque wrench
• Cleaning supplies (MAF cleaner, cloth)

2. Inspect and Repair Air Intake System

• Step 1: Visually inspect all air intake hoses for cracks or disconnections.
• Step 2: Use a vacuum gauge to check for vacuum leaks. Connect the gauge to a vacuum source and look for readings below the normal range.
• Step 3: Replace any damaged hoses and recheck for leaks.

3. Clean or Replace MAF Sensor

• Step 1: Locate the MAF sensor in the air intake duct.
• Step 2: Disconnect the electrical connector and remove the sensor using a socket set.
• Step 3: Spray MAF cleaner onto the sensor element and allow it to dry completely before reinstallation.
• Step 4: Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Step 1: Connect the fuel pressure gauge to the fuel rail.
• Step 2: Turn the ignition key to the "ON" position without starting the engine and check the fuel pressure reading.
• Step 3: If pressure is below specifications, inspect the fuel pump and fuel filter. Replace if necessary.

5. Inspect Fuel Injectors

• Step 1: Remove the fuel rail to access the fuel injectors.
• Step 2: Inspect the injectors for clogs or leaks. Clean using appropriate injector cleaner or replace if necessary.
• Step 3: Reinstall the rail and ensure all connections are secure.

6. Verify Exhaust Integrity

• Step 1: Inspect the exhaust system for any leaks, particularly before the oxygen sensors.
• Step 2: Repair any found leaks using exhaust sealant or replace damaged components.