how to fix P0300 misfire code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0300 engine misfire in Tesla Model S Plaid/Refresh. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Ensure the vehicle is parked on a level surface and the parking brake is engaged.
• Disconnect the high-voltage battery by following the manufacturer's safety procedures to prevent any electrical hazards.
• Gather tools and parts needed for the repair.

2. Inspect and Replace Faulty Components

A. Ignition System

• Tools Required: Socket set, torque wrench, ignition coil puller
• Remove the engine cover if necessary.
• Disconnect the wiring harness from the ignition coils.
• Remove the ignition coils using the socket set.
• Inspect the ignition coils for cracks or damage; replace if defective.
• Replace spark plugs if they show signs of wear (check gap specifications).
• Reinstall new ignition coils, ensuring they are torqued to the manufacturer's specifications.

B. Fuel System

• Tools Required: Fuel pressure gauge, fuel line disconnect tool
• Check fuel pressure at the fuel rail; it should meet manufacturer specifications.
• If fuel pressure is low, inspect the fuel pump and replace if necessary.
• Inspect fuel injectors for clogs or leaks; clean or replace them as needed.
• Reconnect all fuel lines securely.

3. Software Update

• Connect the vehicle to Tesla's service tool or visit a Tesla service center to ensure the software is up to date.
• Follow any prompts to install updates, which can resolve software-related misfires.