how to deal with a P0300 code on my BMW 3 Series F30/F31 (2012-2019)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a flat surface and engage the parking brake.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Spark Plug Inspection and Replacement

• Remove the ignition coils by unscrewing the retaining bolts and carefully pulling them out.
• Extract the spark plugs using a spark plug socket and ratchet.
• Inspect the spark plugs for wear; replace any that are fouled or damaged.
• Install new spark plugs, tightening them to the manufacturer's specified torque (typically around 15-20 Nm).
• Reinsert the ignition coils and secure them with the retaining bolts.

3. Ignition Coil Testing

• Use a multimeter to test the resistance of each ignition coil according to specifications (usually between 0.4 - 2.0 ohms).
• Replace any coils that show an out-of-spec reading.
• Reconnect the ignition coils after inspection or replacement.

4. Fuel Injector Inspection

• Remove the fuel rail if necessary to access the injectors.
• Check each fuel injector for proper operation using a noid light or injector tester.
• Replace any malfunctioning injectors.
• Reinstall the fuel rail and ensure all connections are secure.

5. Vacuum Leak Check

• Start the engine and listen for unusual hissing sounds indicating vacuum leaks.
• Use a smoke machine or carburetor cleaner to identify leaks at hoses and gaskets.
• Replace any damaged vacuum hoses or gaskets.

6. MAF Sensor Cleaning or Replacement

• Disconnect the MAF sensor electrical connector.
• Remove the MAF sensor from the intake duct.
• Clean the sensor with MAF cleaner spray; avoid touching the sensor elements.
• Reinstall the MAF sensor and reconnect the connector.