how to fix P0300 misfire code in Honda CR-V Fifth Generation (2017-2022)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Replace Spark Plugs

• Tools Required: Spark plug socket, ratchet, torque wrench, dielectric grease.
• Sub-steps:
  1. Disconnect the negative battery terminal.
  2. Remove the engine cover if present.
  3. Remove the ignition coil by disconnecting the electrical connector and using the socket to remove the retaining bolts.
  4. Carefully pull out the spark plug using a spark plug socket.
  5. Inspect the old spark plug for signs of wear or fouling.
  6. Install the new spark plug, using dielectric grease on the threads, and torque to the manufacturer’s specifications (typically around 13 lb-ft).
  7. Reinstall the ignition coil and reconnect the electrical connector.

3. Test Ignition Coils

• Tools Required: Multimeter.
• Sub-steps:
  1. Measure the resistance of each ignition coil to ensure they meet specifications (typically 0.4-2.0 ohms for primary resistance).
  2. If any coil is out of spec, replace it with a new one.
  3. Reinstall any removed components and reconnect the battery terminal.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Sub-steps:
  1. Locate the fuel rail and attach the fuel pressure gauge.
  2. Turn the ignition to the ON position (do not start) and check the fuel pressure; it should be within specifications (usually around 40-50 psi).
  3. If pressure is low, inspect the fuel pump and filter for issues and replace as necessary.

5. Inspect Air Intake System

• Tools Required: Screwdrivers, pliers.
• Sub-steps:
  1. Visually inspect the air intake hoses for cracks or loose connections.
  2. Clean or replace the air filter if it is dirty.
  3. Ensure the mass air flow (MAF) sensor is clean; use MAF cleaner if necessary.

6. Check for Vacuum Leaks

• Tools Required: Smoke machine or carburetor cleaner.
• Sub-steps:
  1. If using a smoke machine, introduce smoke into the intake system and check for leaks.
  2. If using carburetor cleaner, spray around the intake manifold and vacuum hoses while the engine is idling; a change in RPM indicates a leak.
  3. Repair or replace any damaged hoses or gaskets found during inspection.