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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Basic hand tools (screwdrivers, pliers), smoke tester (if available)
• Check hoses and gaskets connected to the intake manifold for cracks or disconnections.
• Use a smoke tester to identify any hidden vacuum leaks; repair or replace any faulty components.

3. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner (specific cleaner), screwdriver or socket set
• Remove the MAF sensor from the air intake duct.
• Spray the MAF sensor with a dedicated cleaner, avoiding any metal parts.
• Allow it to dry completely before reinstalling.
• If the MAF sensor is damaged, replace it with a new one, ensuring it is properly calibrated.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel pressure test port on the fuel rail.
• Connect the fuel pressure gauge and turn the ignition to the "ON" position (do not start).
• Verify that the fuel pressure is within specifications (typically around 40-50 psi for Honda Civics).
• If pressure is low, inspect the fuel pump and filter for issues.

5. Inspect Fuel Injectors

• Tools Required: Fuel injector cleaner, multimeter (if testing electrical components)
• Remove the fuel injectors and inspect for blockages or leaks.
• Clean the injectors using a fuel injector cleaner or replace them if necessary.
• If electrical, use a multimeter to check for proper voltage and resistance.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0171 code.
• Start the engine and allow it to idle.