how to fix Honda Accord 10th Generation (2018-2022) emissions test failure

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, basic hand tools, safety goggles, gloves.
• Ensure the vehicle is parked on a level surface and the engine is cool before starting repairs.

2. Address Error Codes

• Sub-steps:
  1. Connect the OBD-II scanner to the vehicle’s diagnostic port.
  2. Retrieve and document any error codes related to emissions (e.g., P0420 for catalytic converter efficiency).
  3. Research the codes to determine specific repairs needed.

3. Replace Faulty Components

• Sub-steps:
  1. If the oxygen sensors are faulty, disconnect the battery.
  2. Remove the old oxygen sensors using a socket wrench.
  3. Install new oxygen sensors, ensuring proper torque specifications (typically 30 lb-ft).
  4. Reconnect the battery.

4. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover if necessary.
  2. Disconnect the ignition coils and remove the spark plugs using a spark plug socket.
  3. Inspect spark plugs for wear; replace with OEM specifications if necessary.
  4. Reinstall the ignition coils and engine cover.

5. Clean or Replace Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail according to the service manual.
  2. Clean the fuel injectors using a fuel injector cleaning kit or replace them if they are clogged.
  3. Reassemble the fuel rail and ensure all connections are tight.

6. Check and Replace the Catalytic Converter (if necessary)

• Sub-steps:
  1. Inspect the catalytic converter for physical damage.
  2. If damaged, unbolt the old catalytic converter from the exhaust system.
  3. Install a new catalytic converter, ensuring proper alignment and torque specifications (typically 25 lb-ft).