how to resolve P0301 code on my Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a level surface and engage the parking brake.
• Disconnect the negative terminal of the battery to ensure safety.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1.
  • Tools Required: Socket set, ratchet.
  • Safety Warning: Ensure the engine is cool before starting work.
• Remove the spark plug using a spark plug socket.
• Inspect the spark plug for wear, carbon buildup, or damage. If needed, replace with an OEM equivalent spark plug.
• Torque the new spark plug to the manufacturer's specification (typically around 13 lb-ft).
• Reinstall the ignition coil.

3. Test and Replace Ignition Coil (if necessary)

• Swap the ignition coil from cylinder 1 with another cylinder (e.g., cylinder 2).
• Clear the P0301 code using the OBD-II scanner.
• Start the engine and check if the misfire code follows the ignition coil.
• If the misfire code appears for the swapped cylinder, replace the ignition coil for cylinder 1.

4. Inspect and Replace Fuel Injector (if necessary)

• Disconnect the fuel injector connector for cylinder 1.
• Using a multimeter, check the injector resistance; it should typically be around 12-16 ohms.
• If the injector is faulty, replace it with a new one.
• Reconnect the fuel injector connector.

5. Conduct Compression Test

• Remove the spark plug from cylinder 1.
• Insert a compression gauge into the spark plug hole and crank the engine for a few seconds.
• Compare the reading to the specifications (usually around 180-200 psi).
• If the compression is low, further diagnostics may be required (e.g., valve issues).