how can I resolve the P0301 error code on my BMW 5 Series G30/G31 (2017-2024)?

Solution

1. Preparation

• Gather tools and parts needed for repair.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shock.

2. Replace Spark Plug

• Tools Required: Spark plug socket, ratchet, torque wrench
• Remove the ignition coil from cylinder 1:
  1. Unplug the electrical connector from the ignition coil.
  2. Remove the bolts securing the ignition coil and gently pull it out.
• Remove the spark plug:
  1. Use a spark plug socket to unscrew and remove the spark plug.
  2. Inspect the old spark plug for wear or fouling.
• Install the new spark plug:
  1. Apply a small amount of anti-seize compound on the threads of the new spark plug.
  2. Hand-tighten the spark plug into the cylinder head, then torque it to the manufacturer’s specification (typically around 20 Nm or 15 lb-ft).

3. Replace Ignition Coil

• Tools Required: Socket set
• Install the new ignition coil:
  1. Position the new ignition coil over the spark plug and push down until it clicks into place.
  2. Reinstall the securing bolts and tighten to specification (typically around 10 Nm or 7.5 lb-ft).
  3. Reconnect the electrical connector.

4. Inspect/Replace Fuel Injector

• Tools Required: Fuel injector puller (if necessary), cleaning solvent
• If the injector was found faulty:
  1. Disconnect the fuel line and electrical connector from the injector.
  2. Remove the retaining clips and pull the injector from the rail.
  3. Install a new or cleaned injector by reversing the removal steps.

5. Reassemble and Final Checks

• Reconnect the negative battery terminal.
• Check all connections for security and leaks.
• Start the engine and allow it to idle.