why does my Honda Pilot YF3 (2016-2022) engine idle rough when cold

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to ensure safety.
• Allow the engine to cool if previously running.

2. Inspect and Clean the Idle Air Control Valve

• Tools Required: Socket set, cleaning solvent or throttle body cleaner, soft brush.
• Sub-steps:
  1. Locate the idle air control valve (IAC) on the throttle body.
  2. Remove the electrical connector from the IAC.
  3. Unbolt the IAC using the socket set.
  4. Clean the IAC with the solvent and brush, removing carbon buildup.
  5. Reinstall the IAC and reconnect the electrical connector.

3. Replace Spark Plugs

• Tools Required: Socket set, torque wrench.
• Sub-steps:
  1. Remove the engine cover (if applicable).
  2. Disconnect the ignition coils by removing their connectors.
  3. Unbolt and remove the ignition coils.
  4. Use a socket wrench to remove the old spark plugs.
  5. Install new spark plugs, ensuring proper gap settings.
  6. Torque the spark plugs to the manufacturer's specifications (typically around 13 lb-ft).
  7. Reinstall the ignition coils and reconnect them.
  8. Reattach the engine cover.

4. Test and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Sub-steps:
  1. Locate the fuel pressure test port on the fuel rail.
  2. Attach the fuel pressure gauge to the port.
  3. Turn the ignition to the "ON" position without starting the engine to check for pressure.
  4. Compare the reading to the specified pressure (usually around 30-50 psi).
  5. If pressure is low, inspect the fuel pump and fuel filter for issues.