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

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Disconnect the ignition coil connector from the spark plug of cylinder 1.
  3. Remove the ignition coil using a socket wrench.
  4. Unscrew and remove the spark plug with a spark plug socket.
  5. Inspect the spark plug for wear, carbon buildup, or damage; replace if necessary.
  6. Gap the new spark plug to manufacturer specifications (typically around 0.032 inches).
  7. Install the new spark plug and torque to the manufacturer's specification (usually around 18-22 lb-ft).
  8. Reinstall the ignition coil and reconnect the connector.

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug was not the issue, remove the ignition coil for cylinder 1 as previously described.
  2. Inspect the ignition coil for cracks or damage.
  3. Replace with a new ignition coil if necessary.
  4. Reinstall the ignition coil and reconnect the connector.

4. Check Compression

• Sub-steps:
  1. Remove the spark plugs from all cylinders to allow for easier cranking.
  2. Insert the compression gauge into the spark plug hole of cylinder 1.
  3. Crank the engine and record the compression reading.
  4. Compare the reading to the manufacturer’s specifications (typically around 140-200 psi).
  5. If compression is low, further diagnostics on the engine internals may be needed.

5. Inspect Fuel Injector

• Sub-steps:
  1. Remove the fuel rail covering the injector for cylinder 1.
  2. Disconnect and remove the fuel injector for cylinder 1.
  3. Test the injector operation with a noid light or multimeter for proper resistance.
  4. Replace if faulty and reinstall the fuel injector.
  5. Reattach the fuel rail and ensure there are no leaks.