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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the vehicle is parked on a flat surface and secured with wheel chocks.

2. Inspect and Replace Spark Plugs

• Remove the engine cover if applicable.
• Carefully remove the spark plug wires or ignition coils from the spark plugs.
• Using a spark plug socket, remove the old spark plugs. Inspect them for wear or carbon buildup.
• Install new spark plugs, ensuring the correct gap as specified in the owner’s manual.
• Torque the spark plugs to the manufacturer's specifications (usually around 12-15 lb-ft).

3. Inspect and Replace Ignition Coils

• If any ignition coils showed signs of damage, remove them by unscrewing the retaining bolts or clips.
• Install new ignition coils, ensuring they are seated properly.
• Reconnect the spark plug wires or connectors securely.

4. Fuel System Inspection

• Use a fuel pressure gauge to check the fuel pressure at the fuel rail; it should meet manufacturer specifications.
• If pressure is low, inspect the fuel pump and fuel filter for blockage or failure.
• Clean or replace fuel injectors if necessary.

5. Check for Vacuum Leaks

• Inspect all vacuum hoses and connections for cracks or disconnections.
• Use a smoke machine or carburetor cleaner to help identify any leaks around the intake manifold or throttle body.
• Repair or replace any damaged hoses.