how to diagnose a P0455 code on Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle battery to ensure safety while working on electrical components.

2. Inspect and Replace the Gas Cap

• Remove the gas cap and inspect for cracks or wear.
• If damaged, replace with a new OEM gas cap.
• Reinstall the gas cap and ensure it clicks into place securely.

3. Repair or Replace EVAP Hoses

• Identify any cracked or damaged hoses connected to the EVAP system.
• Use a socket set to remove any necessary components to access the hoses.
• Replace damaged hoses with OEM parts, securing all connections tightly.

4. Smoke Test the EVAP System

• Connect a smoke machine to the EVAP service port.
• Activate the smoke machine and observe for smoke leaks from hoses, canister, or connections.
• Repair any leaks found by replacing affected components.

5. Test and Replace EVAP Purge Valve

• Locate the EVAP purge valve; typically found near the intake manifold.
• Disconnect the electrical connector and apply power to the valve to test operation; it should click and open.
• If faulty, replace the purge valve with an OEM replacement.

6. Clear Codes and Test Drive

• Reconnect the battery and use an OBD-II scanner to clear the P0455 code.
• Perform a test drive to monitor for any reoccurrence of the check engine light.