how to fix the P0301 misfire code on my BMW 3 Series F30/F31 (2012-2019)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool down before starting work.

2. Replace Spark Plug and Ignition Coil

1. Remove Engine Cover (if applicable)
   • Use a socket set to remove any screws or bolts securing the engine cover.
2. Remove Ignition Coil
   • Disconnect the electrical connector from the ignition coil.
   • Use a socket to remove the bolt(s) securing the ignition coil and pull it out.
3. Replace Spark Plug
   • Use a spark plug socket to remove the spark plug from cylinder 1.
   • Inspect the old spark plug for signs of wear or damage.
   • Install a new spark plug, using the manufacturer's specified gap.
   • Torque the spark plug to the manufacturer's specifications (typically around 18-22 ft-lbs).
4. Reinstall Ignition Coil
   • Place the new ignition coil into the cylinder head and secure it with the bolt(s).
   • Reconnect the electrical connector.

3. Inspect and Repair Fuel Injector

1. Remove Fuel Injector
   • Remove any necessary components to access the fuel rail, such as the intake manifold or fuel rail cover.
   • Disconnect the fuel line (safety first: relieve fuel pressure).
   • Remove the fuel injector retaining clips and pull out the injector.
2. Clean or Replace Injector
   • Inspect the fuel injector for clogs; clean if necessary or replace it with a new one.
3. Reinstall Fuel Injector
   • Insert the injector back into the fuel rail and secure it with clips.
   • Reconnect the fuel line, ensuring a tight fit.

4. Final Checks

• Reconnect the battery.
• Start the engine and check for any leaks or abnormal noises.