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

Solution

1. Preparation

• Gather tools and parts.
• Ensure the engine is cool.
• Disconnect the negative battery terminal to avoid electrical issues.

2. Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Locate cylinder 1 spark plug (typically at the front of the engine).
  3. Use a spark plug socket to remove the old spark plug.
  4. Inspect the old spark plug for signs of wear or fouling.
  5. Install a new spark plug, using the manufacturer’s specific torque specifications (usually around 18-22 ft-lbs).
  6. Reinstall the engine cover.

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. Remove the ignition coil cover.
  2. Disconnect the electrical connector from the ignition coil in cylinder 1.
  3. Remove the ignition coil using a socket.
  4. If swapping with another coil, install the known good coil in cylinder 1.
  5. Reconnect the electrical connector.
  6. Clear the DTC and test drive the vehicle.

4. Test and Replace Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector in cylinder 1.
  2. Using a multimeter, check the resistance of the fuel injector (should match manufacturer specs).
  3. If faulty, remove the fuel rail and replace the injector.
  4. Reinstall the fuel rail and reconnect all connectors.
  5. Clear the DTC and test the vehicle.

5. Compression Test (if necessary)

• Sub-steps:
  1. Remove the spark plug from cylinder 1.
  2. Insert a compression tester into the spark plug hole.
  3. Crank the engine and record the compression reading.
  4. Compare to manufacturer specifications. If low, further diagnosis may be required.