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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a flat surface with the engine off and cool.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover (if applicable) by unscrewing any bolts or clips.
  2. Disconnect the ignition coil connector for cylinder 1.
  3. Remove the ignition coil by unscrewing the retaining bolt and pulling it upward.
  4. Use a spark plug socket and ratchet to remove the spark plug from cylinder 1.
  5. Inspect the spark plug for signs of wear, such as excessive carbon buildup or damage.
  6. Install a new spark plug, ensuring it is gapped correctly to the manufacturer's specifications (typically around 0.030 inches).
  7. Reinstall the ignition coil and reconnect the wiring harness.

3. Inspect and Test Ignition Coil

• Sub-steps:
  1. Use a multimeter to check the primary and secondary resistance of the ignition coil. Compare with specifications found in the service manual.
  2. If the resistance is out of spec, replace the ignition coil with a new one.

4. Test Fuel Injector

• Sub-steps:
  1. Remove the fuel rail cover (if applicable) to access the fuel injectors.
  2. Check the electrical connector of the fuel injector for cylinder 1 for proper connection.
  3. Use a noid light to verify that the injector is receiving the correct signal.
  4. If the injector is not functioning, replace it with a new fuel injector.

5. Conduct Compression Test

• Sub-steps:
  1. Remove the spark plug from cylinder 1.
  2. Insert the compression tester into the spark plug hole.
  3. Crank the engine for about 5-7 seconds and record the compression reading.
  4. Compare the reading to the manufacturer's specifications. If the compression is low, further investigation into engine internals may be required.