how to diagnose P0301 misfire code in Honda Accord 9th Generation (2013-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1.
• Unscrew and remove the spark plug using a spark plug socket.
• Inspect the spark plug for damage or excessive wear.
• If necessary, replace the spark plug with a new one (use OEM specifications for gap).
• Reinstall the ignition coil and reconnect the battery.

3. Test and Replace Ignition Coil

• If the spark plug is in good condition, swap the ignition coil from cylinder 1 with another cylinder.
• Clear the trouble codes and run the engine to see if the P0301 code returns.
• If the code follows the ignition coil, replace the faulty coil with a new one.

4. Perform Compression Test

• Remove the spark plug from cylinder 1.
• Insert the compression tester into the spark plug hole and crank the engine.
• Note the compression reading; it should be within the manufacturer's specified range.
• If the reading is low, further engine disassembly may be needed for inspection.

5. Inspect Fuel Injector

• Remove the fuel rail to access the fuel injector for cylinder 1.
• Check for proper operation by using a multimeter to measure resistance.
• Clean or replace the fuel injector if it is found to be faulty.