how to diagnose Honda Accord 10th Generation (2018-2022) P0302 misfire code?

Solution

1. Preparation

• Gather tools: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, and fuel injector cleaner.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Spark Plug

• Remove engine cover if applicable.
• Using a socket wrench, carefully remove the spark plug from cylinder 2.
• Inspect the spark plug for signs of damage or excessive wear. Replace if necessary.
• Torque the new spark plug to the manufacturer’s specification (typically around 13 lb-ft for Honda).
• Reconnect the spark plug wire or coil.

3. Check and Replace Ignition Coil

• Disconnect the ignition coil harness for cylinder 2.
• Remove the ignition coil using a socket wrench.
• Test the ignition coil with a multimeter for proper resistance.
• If faulty, replace the ignition coil with a new one, ensuring it is properly seated.
• Reconnect the ignition coil harness.

4. Inspect and Clean Fuel Injector

• Remove the fuel injector from cylinder 2 by disconnecting the electrical connector and fuel line.
• Check for clogs and clean the injector using fuel injector cleaner.
• If the injector is faulty, replace it with a new one and reconnect it properly.

5. Compression Test

• Remove the spark plug from cylinder 2.
• Install the compression tester into the spark plug hole.
• Crank the engine and note the compression reading. It should be within the manufacturer's specifications (typically around 190-210 psi).
• If compression is low, further inspection of engine internals may be necessary.