how to fix P0301 misfire code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0301 cylinder 1 misfire in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and materials: OBD-II scanner, socket set, torque wrench, spark plug socket, compression tester, dielectric grease.
• Disconnect the vehicle from the charging station and ensure the vehicle is powered off.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover (if applicable).
  2. Disconnect the electrical connectors from the ignition coils.
  3. Remove the ignition coils by unscrewing them using the socket set.
  4. Use the spark plug socket to remove the spark plug from cylinder one.
  5. Inspect the spark plug for signs of wear or fouling; replace if necessary (should be replaced every 30,000-50,000 miles).
  6. Apply a small amount of dielectric grease to the spark plug threads and install the new spark plug, torqueing to the manufacturer’s specification (typically 18 lb-ft).
  7. Reinstall the ignition coils and reconnect the electrical connectors.

3. Check and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug is in good condition, swap the ignition coil from cylinder one with another cylinder.
  2. Clear the P0301 code using the OBD-II scanner.
  3. Test drive the vehicle to see if the misfire code reappears; if it does, replace the ignition coil.

4. Inspect Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder one.
  2. Check for proper voltage and resistance using a multimeter.
  3. If the injector is faulty, replace it by removing the fuel rail (ensure proper fuel handling procedures).
  4. Install the new injector and reconnect the connector.

5. Compression Test

• Sub-steps:
  1. Remove the spark plug from cylinder one again.
  2. Insert the compression tester into the spark plug hole.
  3. Crank the engine to obtain the compression reading.
  4. Compare the reading to the manufacturer’s specifications; if it is below the acceptable range, further engine repair may be necessary.