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

Solution

1. Preparation

• Gather necessary tools and parts. Ensure the engine is cool before starting work.
• Disconnect the battery to avoid any electrical issues during the repair.

2. Replace Spark Plug and Ignition Coil

• Tools Required: Socket set, torque wrench, dielectric grease
• Remove the engine cover (if applicable) to access the ignition components.
• Disconnect the ignition coil connector for cylinder 1 and remove the ignition coil using a socket.
• Remove the spark plug using a spark plug socket; inspect for wear or carbon buildup.
• Install the new spark plug, tightening it to the manufacturer’s specified torque (usually around 18-22 ft-lbs).
• Apply a small amount of dielectric grease to the inside of the ignition coil connector.
• Reinstall the ignition coil and reconnect its connector.

3. Check and Clean the Fuel Injector

• Tools Required: Fuel injector cleaning kit (optional), socket set
• Remove the fuel rail if necessary to access the fuel injector for cylinder 1.
• Inspect the fuel injector for signs of blockage or leaking; clean or replace if necessary.
• Reinstall the fuel injector, ensuring it is seated properly in the rail.

4. Perform Compression Test

• Tools Required: Compression tester
• Remove the spark plug for cylinder 1.
• Insert the compression tester into the cylinder and crank the engine for several seconds.
• Record the compression reading and compare it to the manufacturer specifications (usually around 120-200 psi).
• If the compression is low, further investigation is needed for potential valve or head gasket issues.