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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, basic hand tools, torque wrench.
• Disconnect the vehicle's 12V battery negative terminal to prevent electrical shock.

2. Inspect Ignition Components

• Sub-steps:
  1. Remove the engine cover to access the ignition coils.
  2. Disconnect the ignition coil connectors.
  3. Remove the ignition coils using a socket set.
  4. Inspect the coils for cracks or carbon tracking.
  5. Check the spark plugs for wear and carbon buildup; replace if necessary.

3. Test Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition key to the "on" position without starting the engine and check pressure readings.
  3. If pressure is below specifications (consult the service manual), inspect the fuel pump and filter for clogs or failures.

4. Battery and Electrical System Check

• Sub-steps:
  1. Use a multimeter to check battery voltage (should be around 12.6V for a fully charged battery).
  2. Inspect for loose or corroded battery terminals and clean them if necessary.
  3. If battery voltage is low, recharge or replace the battery.

5. Update Software

• Sub-steps:
  1. Connect the vehicle to Wi-Fi.
  2. Navigate to the software update section on the touchscreen.
  3. Follow prompts to download and install any available updates.

6. Reassemble and Reconnect

• Sub-steps:
  1. Reinstall ignition coils and connect their wiring harnesses.
  2. Replace the engine cover.
  3. Reconnect the 12V battery negative terminal.
  4. Clear the trouble codes using the OBD-II scanner.