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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, fuel pressure gauge.
• Ensure the vehicle is parked on a level surface and is in "Park" mode.

2. Replace Spark Plugs

1. Disconnect the high-voltage battery if necessary for safety.
2. Remove engine cover (if applicable) using the socket set.
3. Carefully remove the spark plug wire or ignition coil from each spark plug.
4. Use a spark plug socket to remove the old spark plugs.
5. Inspect the old plugs for wear and gap; compare with specifications.
6. Install new spark plugs, ensuring proper torque (typically 12-15 Nm).
7. Reconnect the ignition coils or spark plug wires.

3. Test and Replace Ignition Coils (if necessary)

1. Disconnect the battery before working on ignition components.
2. Remove ignition coils from the engine.
3. Test each coil with a multimeter (check for resistance values per manufacturer specifications).
4. Replace any faulty ignition coils with new ones.
5. Reinstall ignition coils securely.

4. Inspect and Clean Fuel Injectors

1. Perform a fuel pressure test to ensure adequate fuel delivery.
2. If low pressure is detected, check the fuel pump and filter.
3. Remove fuel injectors and inspect for clogs.
4. Clean injectors using an ultrasonic cleaner or replace if necessary.
5. Reinstall injectors and ensure proper sealing.

5. Check for Vacuum Leaks

1. Visually inspect all vacuum lines and intake gaskets.
2. Use a smoke machine or carburetor cleaner to detect leaks.
3. Replace any damaged vacuum hoses or gaskets as needed.