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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, fuel pressure gauge, multimeter, compression tester.
• Ensure the vehicle is parked on a flat surface and the engine is cool. Disconnect the battery to prevent electrical shock.

2. Inspect and Replace Spark Plugs

• Remove the engine cover if present.
• Using the socket set, remove the spark plug wires or ignition coils.
• Unscrew the spark plugs using a spark plug socket.
• Inspect the spark plugs for fouling or excessive wear. Replace them with OEM-spec plugs if necessary.
• Reinstall the spark plugs and ignition coils, ensuring they are properly torqued to manufacturer specifications.

3. Inspect and Replace Ignition Coils

• If spark plugs are in good condition, check the ignition coils for signs of failure (cracks or corrosion).
• Disconnect the ignition coil connectors and remove the coils using the socket set.
• Replace any faulty ignition coils with new ones, ensuring they are compatible with the Tesla Model 3 Highland.
• Reconnect the connectors securely.

4. Check for Vacuum Leaks

• Inspect all vacuum lines for cracks or disconnections.
• Use a smoke machine or carburetor cleaner around the intake manifold and hoses to detect leaks.
• Replace any damaged hoses or reseal any leaks found.

5. Final Checks

• Reconnect the battery.
• Clear the error codes using the OBD-II scanner.
• Start the engine and let it idle while monitoring for any misfires or abnormalities.