how to fix P0301 misfire code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a flat surface and ensure the engine is cool.
• Disconnect the battery negative terminal to prevent electrical shock.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1:
  • Use a socket set to remove the bolts securing the ignition coil.
  • Carefully pull the ignition coil straight out to avoid damaging the connector.
• Remove the spark plug:
  • Use a spark plug socket and ratchet to unscrew and remove the spark plug from cylinder 1.
• Inspect the spark plug for wear or carbon buildup.
• Replace with a new spark plug as per manufacturer specifications (use OEM parts when possible).
  • Torque the spark plug to the manufacturer's recommended value (usually around 18-22 lb-ft).
• Reinstall the ignition coil and ensure it is secured properly.

3. Inspect and Replace Ignition Coil

• If the ignition coil appears damaged or faulty, replace it:
  • Remove the old ignition coil as described above.
  • Install the new ignition coil for cylinder 1.
  • Ensure proper seating and secure it with the original bolts.

4. Inspect Fuel Injector

• Check the fuel injector for cylinder 1:
  • Disconnect the electrical connector and fuel line carefully.
  • Remove the fuel injector using the appropriate tool.
• Inspect for debris or clogging, and replace if necessary.
• Reinstall the fuel injector and reconnect the fuel line and electrical connector.

5. Perform Compression Test (if needed)

• If misfire persists, perform a compression test:
  • Remove the spark plug and install the compression gauge.
  • Crank the engine and note the compression reading.
• Compare readings against manufacturer specifications; repair as needed (e.g., replace piston rings or valves).