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

Solution

1. Preparation

• Gather tools and parts before starting the repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down before beginning work.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover if necessary using a socket set.
  2. Disconnect the ignition coils by unplugging the electrical connectors.
  3. Remove the ignition coils from the spark plugs.
  4. Unscrew the old spark plugs using a spark plug socket.
  5. Inspect the spark plugs for wear; replace with OEM-spec plugs if needed (Torque to manufacturer specifications).

3. Inspect and Replace Ignition Coils

• Sub-steps:
  1. If any ignition coils are damaged or show signs of failure, remove them from the cylinder head.
  2. Install new ignition coils (ensure they match OEM specifications).
  3. Reconnect the electrical connectors firmly.

4. Check Fuel System

• Sub-steps:
  1. Temporarily connect the fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the "ON" position (do not start the engine) and check the fuel pressure (should be within specified range).
  3. If pressure is low, inspect and replace the fuel filter and fuel pump if necessary.
  4. Reconnect all lines and remove the fuel gauge.

5. Inspect for Vacuum Leaks

• Sub-steps:
  1. Use a smoke tester to introduce smoke into the intake system.
  2. Inspect for any visible smoke escaping from vacuum lines or intake manifold.
  3. Replace any damaged vacuum hoses or gaskets.

6. Reconnect Battery

• Reconnect the negative battery terminal.
• Clear the P0300 code using the OBD-II scanner.