my Honda Civic 10th Generation (2016-2021) has a P0301 code, what does this mean

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal for safety.

2. Inspect and Replace Spark Plug

• Tools Needed: Socket set, torque wrench, dielectric grease.
• Remove the ignition coil from cylinder 1:
  1. Unplug the electrical connector.
  2. Remove the mounting bolts.
  3. Carefully lift out the ignition coil.
• Remove the spark plug:
  1. Use a spark plug socket to unscrew and remove the spark plug.
• Inspect the spark plug for wear (electrode condition, carbon fouling, etc.):
  1. If damaged, replace with a new spark plug.
  2. Apply dielectric grease to the spark plug threads and install it to the specified torque (typically 13-16 ft-lbs).
• Reinstall the ignition coil:
  1. Tighten the mounting bolts to the manufacturer's specifications.
  2. Reconnect the electrical connector.

3. Test Fuel Injector

• Tools Needed: Fuel pressure gauge, multimeter.
• Check the electrical connector on the cylinder 1 fuel injector:
  1. Use a multimeter to test for voltage while cranking the engine.
• If no voltage is detected, trace wiring back to the ECM or check for blown fuses.
• If voltage is present, use a fuel pressure gauge to ensure proper fuel delivery.

4. Compression Test

• Tools Needed: Compression tester.
• Insert the compression tester into the spark plug hole of cylinder 1:
  1. Crank the engine and record the compression reading.
  2. Compare the reading to the manufacturer’s specifications (typically between 170-210 psi).
• If the reading is low, further investigate for possible causes such as a blown head gasket or valve issues.

5. Inspect for Vacuum Leaks

• Tools Needed: Smoke machine (optional) or carb cleaner.
• Visually inspect all vacuum hoses connected to the intake manifold:
  1. Look for cracks or disconnections.
  2. If using a smoke machine, introduce smoke to check for leaks.
• Repair or replace any damaged vacuum hoses.