how to fix P0300 random misfire code in my Genesis G70 IG (2017-2023)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to ensure safety during repairs.

2. Inspect and Replace Spark Plugs

• Tools Required: Socket set, torque wrench, gap gauge, spark plug socket.
• Remove the ignition coil covers to access the spark plugs.
• Use the socket set to remove the spark plugs.
• Inspect each plug for wear; replace if necessary, ensuring the gap is set to the manufacturer's specification (typically around 0.028-0.031 inches).
• Install new spark plugs and torque to the recommended specification (usually around 13-15 lb-ft).

3. Check and Replace Ignition Coils

• Tools Required: Socket set.
• Remove the ignition coils from the spark plugs.
• Inspect for cracks or damage.
• If any coils are faulty, replace them with new ones, ensuring they are the correct part for the Genesis G70 (IG).
• Reinstall ignition coils securely.

4. Inspect Fuel Injectors

• Tools Required: Injector removal tool (if necessary).
• Disconnect the fuel injector connectors.
• Remove the fuel rail if necessary to access the injectors.
• Inspect injectors for clogs or leaks. Clean or replace as needed.
• Reinstall the fuel rail and reconnect the injectors.

5. Test Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Attach the fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the "ON" position (do not start) and check the pressure; it should match manufacturer specifications (usually around 50-60 psi).
• If pressure is low, check the fuel pump and filter for issues.

6. Vacuum Leak Test

• Tools Required: Smoke machine or vacuum gauge.
• Use a smoke machine to test for vacuum leaks around intake manifold gaskets and hoses.
• Repair any identified leaks by replacing gaskets or hoses as needed.