how to fix P0171 code on Honda Accord 9th Generation (2013-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool if it has been running.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps, screwdriver
• Inspect all vacuum hoses for cracks or disconnections.
• Replace any damaged hoses and ensure all connections are secure.

3. Clean or Replace the MAF Sensor

• Tools Required: MAF cleaner, screwdriver
• Remove the MAF sensor from the air intake duct.
• Spray MAF cleaner onto the sensor elements without touching them. Allow it to dry.
• Reinstall the sensor ensuring it’s properly seated and secured.

4. Test and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition to the “ON” position (do not start the engine) and check the fuel pressure. It should be within manufacturer specifications (usually 40-50 psi).
• If pressure is low, check the fuel pump and filter for issues.

5. Inspect and Clean Fuel Injectors

• Tools Required: Injector cleaning kit or replace injectors if necessary
• If injectors are dirty, follow the cleaning kit instructions. If they are leaking or malfunctioning, replace them with new units.

6. Replace Faulty O2 Sensor

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Locate the upstream O2 sensor on the exhaust manifold.
• Disconnect the wiring harness and remove the sensor using an O2 sensor socket.
• Install the new O2 sensor and torque it to manufacturer specifications (usually around 30 lb-ft).
• Reconnect the wiring harness securely.