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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the engine is cool before beginning work.

2. Replace Spark Plug

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the ignition coil from cylinder 1 by unscrewing the bolts.
• Carefully pull out the spark plug using a spark plug socket.
• Inspect the old spark plug for wear; replace it if necessary.
• Install the new spark plug and torque it to manufacturer specifications (typically around 18-22 ft-lbs).
• Reattach the ignition coil.

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench.
• If the ignition coil appears damaged, remove it from cylinder 1.
• Test the ignition coil using a multimeter (check for proper resistance).
• If faulty, replace with a new ignition coil and torque it to manufacturer specifications (usually around 10-15 ft-lbs).

4. Inspect and Clean Fuel Injector

• Tools Required: Fuel injector cleaning kit or replacement injector, safety glasses, gloves.
• Remove the fuel rail to access the fuel injector for cylinder 1.
• Inspect the injector for clogs or debris; clean or replace as needed.
• Reinstall the fuel injector and ensure that all connections are secure.

5. Conduct Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 1 and connect the compression tester.
• Crank the engine and record the compression reading.
• Compare the reading to manufacturer specifications; if low, further diagnostics may be required.