how to fix P0300 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 ignition is off.
• Disconnect the 12V battery for safety.

2. Inspect and Replace Spark Plugs

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the engine cover if necessary.
• Using the spark plug socket, carefully unscrew each spark plug.
• Inspect the plugs for wear; replace them if they show signs of damage or wear (e.g., carbon buildup).
• Install new spark plugs by hand to avoid cross-threading, then torque to manufacturer's specifications (typically around 13-15 ft-lbs).

3. Check and Replace Ignition Coils

• Tools Required: Socket set, torque wrench.
• Disconnect the electrical connectors from each ignition coil.
• Remove the bolts securing the ignition coils and carefully pull them from the cylinder head.
• Inspect for cracks or signs of wear and replace if necessary.
• Reinstall the ignition coils and torque the bolts to specifications.

4. Inspect Fuel Injectors

• Tools Required: Fuel pressure gauge, basic hand tools.
• Locate the fuel rail and disconnect the fuel line.
• Attach a fuel pressure gauge to the fuel rail and turn the ignition key to the ON position (do not start the engine) to check fuel pressure.
• If pressure is low, inspect or replace the fuel filter and check for blockage in the fuel lines.
• Remove fuel injectors for cleaning or replacement if they are clogged.

5. Inspect Intake and Vacuum Hoses

• Tools Required: Visual inspection tools.
• Visually inspect all air intake and vacuum hoses for signs of wear, cracks, or disconnections.
• Replace any damaged hoses to ensure proper air-fuel mixture.

6. Reconnect Battery and Clear Codes

• Reconnect the 12V battery.
• Use the OBD-II scanner to clear the P0300 code and any other related codes.
• Start the engine and check for any reoccurrence of the misfire code.