how to fix the P0304 code in my Tesla Model S Plaid/Refresh (2021-present)?

Learn how to diagnose and fix P0304 cylinder 4 misfire in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative terminal of the battery to ensure safety.
• Allow the engine to cool down completely.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Locate cylinder 4 spark plug (refer to service manual for location).
  3. Using the spark plug socket, carefully remove the spark plug.
  4. Inspect the spark plug for wear or carbon buildup; replace if necessary.
  5. Install the new spark plug and torque to the manufacturer’s specifications (typically around 12-15 Nm).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set.
• Sub-steps:
  1. Disconnect the ignition coil connector from cylinder 4.
  2. Remove the ignition coil using the appropriate socket.
  3. Inspect the ignition coil for cracks or damage; replace if necessary.
  4. Install the new ignition coil, ensuring it is seated properly.
  5. Reconnect the ignition coil connector.

4. Inspect and Test Fuel Injector

• Tools Required: Noid light, multimeter.
• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 4.
  2. Use a noid light to check if the injector is receiving a pulse; if not, further diagnose the wiring.
  3. If the injector is faulty, remove it using the appropriate socket.
  4. Install a new fuel injector and reconnect the connector.

5. Reassemble and Clear Codes

• Reinstall any components removed during the process, including engine cover.
• Reconnect the negative terminal of the battery.
• Use the OBD-II scanner to clear codes and reset the check engine light.