how to fix P0301 misfire code on BMW 5 Series G30/G31 (2017-2024)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to prevent any electrical short circuits.
• Ensure the engine is cool before beginning work.

2. Remove the Ignition Coil and Spark Plug

• Tools Required: Socket set, ratchet, extension
• Steps:
  1. Locate the ignition coil for cylinder 1 (refer to the engine layout).
  2. Remove the electrical connector from the ignition coil.
  3. Unbolt the ignition coil using the socket set and remove it from the cylinder head.
  4. Using a spark plug socket, remove the spark plug from cylinder 1.

3. Inspect and Replace Components

• Tools Required: Torque wrench, gap gauge
• Steps:
  1. Inspect the spark plug for signs of wear or fouling; replace if necessary.
  2. Check the gap on the new spark plug using a gap gauge; set it to manufacturer specifications (typically around 0.032-0.036 inches).
  3. Inspect the ignition coil for damage; replace it if resistance measurements are out of range or if physical damage is noted.

4. Reassemble

• Steps:
  1. Install the new spark plug and torque it to manufacturer specifications (usually around 15-25 Nm).
  2. Reinstall the ignition coil and secure it with the bolts.
  3. Reconnect the electrical connector to the ignition coil.

5. Final Checks

• Reconnect the battery.
• Clear the trouble codes using an OBD-II scanner.
• Start the engine and verify that the misfire code does not return.