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.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, gap gauge.
• Remove the ignition coil by unscrewing the retaining bolts or clips.
• Carefully pull the ignition coil out of the spark plug hole.
• Use a socket to remove the old spark plug.
• Inspect the new spark plug for proper gap (usually 0.028-0.032 inches for BMW).
• Install the new spark plug and torque it to the manufacturer's specification (typically 18-22 ft-lbs).
• Reinstall the ignition coil and secure it.

3. Replace Ignition Coil (if necessary)

• Tools Required: Socket set.
• If the ignition coil is faulty, remove it from cylinder 1.
• Install the new ignition coil and secure it properly.
• Reconnect electrical connectors.

4. Test Fuel Injector

• Tools Required: Fuel injector cleaner, multimeter (optional).
• If the injector is clogged, use a fuel injector cleaner according to the product instructions.
• If the injector is not functioning, replace it by disconnecting the harness and unbolting it from the fuel rail.

5. Check for Vacuum Leaks

• Thoroughly inspect all vacuum hoses and the intake manifold gasket for any signs of wear or leaks.
• Replace any damaged hoses or gaskets.