how to fix P0300 misfire code in Tesla Model 3 Highland (2024-present)

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 to prevent electrical shorts.

2. Inspect and Replace Ignition Components

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the wiring harness from each ignition coil.
  3. Remove the ignition coils using a socket set.
  4. Inspect the spark plugs; replace any that show excessive wear or carbon buildup.
  5. Install new spark plugs (if needed) to the manufacturer's torque specifications.
  6. Reinstall the ignition coils and reconnect the wiring harness.

3. Fuel System Inspection

• Sub-steps:
  1. Check fuel injector connectors for damage and ensure they are securely attached.
  2. Use a fuel pressure gauge to test fuel pressure at the rail; compare it to specifications.
  3. If pressure is low, consider replacing the fuel pump or filters.
  4. If injectors are clogged, remove them for cleaning or replacement.

4. Address Any Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum lines for cracks or disconnections.
  2. Using a smoke machine, introduce smoke into the intake system to identify leaks.
  3. Replace damaged vacuum hoses and ensure all connections are secure.

5. Reassemble and Test

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Start the engine and allow it to reach operating temperature.
  3. Monitor the engine for any misfire symptoms or codes.