how to fix the P0301 misfire code on my BMW 5 Series G30/G31 (2017-2024)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to prevent electrical shocks.
• Allow the engine to cool before beginning work.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench.
• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Locate the spark plug for cylinder 1.
  3. Use the spark plug socket to remove the old spark plug.
  4. Inspect the old spark plug for damage.
  5. Apply anti-seize compound to the threads of the new spark plug.
  6. Install the new spark plug and torque it to the manufacturer's specifications (typically around 22 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Ratchet, socket set, torque wrench.
• Sub-steps:
  1. Disconnect the electrical connector from the ignition coil.
  2. Remove the retaining bolts for the ignition coil.
  3. Pull the ignition coil out of the cylinder head.
  4. Install the new ignition coil, ensuring it is seated properly.
  5. Reattach the electrical connector.
  6. Torque the ignition coil bolts to the manufacturer's specifications.

4. Check Fuel Injector

• Tools Required: Multimeter (to test injector resistance).
• Sub-steps:
  1. Disconnect the fuel injector connector.
  2. Test the injector resistance using a multimeter; it should match the manufacturer's specifications.
  3. If faulty, replace the fuel injector.
  4. Reconnect the fuel injector and ensure it is seated correctly.

5. Reassemble and Reconnect

• Replace any components removed for access (engine cover, etc.).
• Reconnect the battery.