how to diagnose Honda Accord 10th Generation (2018-2022) engine misfire issues

Learn to diagnose and fix engine misfire issues (P0300-P0306) in Honda Accord 10th Generation (2018-2022). Step-by-step guide with symptoms and solutions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during repairs.
• Allow the engine to cool down.

2. Inspect and Replace Spark Plugs

• Remove the ignition coil covers using a socket set.
• Disconnect the electrical connectors from each ignition coil.
• Remove the ignition coils and inspect them for damage.
• Remove the spark plugs using a spark plug socket.
• Check the spark plug gaps and replace any plugs that are worn or damaged.
• Install new spark plugs with the correct gap (typically 0.044 inches).
• Reinstall the ignition coils and reconnect the electrical connectors.

3. Check and Replace Ignition Coils

• If any coils showed signs of damage, replace them.
• Remove the faulty ignition coil from the cylinder head.
• Install the new ignition coil and ensure it clicks into place.
• Reconnect the electrical connector.

4. Fuel Injector Inspection and Cleaning

• Remove the fuel rail assembly by disconnecting it from the intake manifold.
• Inspect injectors for clogs or leaks; replace if necessary.
• Clean the fuel injectors using an ultrasonic cleaner or a dedicated fuel injector cleaning kit.
• Reinstall the fuel rail and connect it back to the intake manifold.

5. Compression Test

• Remove all spark plugs for easy access to the cylinders.
• Insert a compression gauge into the spark plug hole of each cylinder.
• Crank the engine to take readings; compare to manufacturer specifications.
• If readings are low, further investigate potential causes (e.g., valve issues, head gasket failure).