how to fix P0301 misfire code on BMW X5 G05 (2019-2024)?

Solution

1. Preparation

• Gather tools and parts needed: OBD-II scanner, torque wrench, socket set, compression tester, replacement spark plug, ignition coil, fuel injector cleaner.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Replace Spark Plug

• Sub-steps:
  1. Disconnect the negative battery terminal to prevent electrical shorts.
  2. Remove engine cover (if applicable) to access spark plug.
  3. Unplug the ignition coil connector for cylinder 1.
  4. Remove the ignition coil using a socket.
  5. Remove the old spark plug using a spark plug socket.
  6. Inspect the spark plug for signs of improper wear; replace if necessary.
  7. Install the new spark plug, tightening to manufacturer specifications (typically 22 ft-lbs for BMW).
  8. Reinstall the ignition coil and reconnect the electrical connector.

3. Inspect and Replace Ignition Coil (if necessary)

• Sub-steps:
  1. If the ignition coil was found faulty during diagnostics, remove it from the engine.
  2. Install the new ignition coil, ensuring it is seated properly.
  3. Reconnect the ignition coil connector.

4. Check and Clean Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Remove the fuel injector from its rail (may require fuel rail removal).
  3. Clean the injector with fuel injector cleaner.
  4. Reinstall the injector, ensuring it is properly seated and sealed.

5. Reassemble and Clear Codes

• Sub-steps:
  1. Reinstall any components removed, including engine cover.
  2. Reconnect the negative battery terminal.
  3. Use the OBD-II scanner to clear the P0301 code.