what should I do if my BMW 5 Series F10/F11 (2010-2017) has a P0301 code

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, fuel injector cleaning kit.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Remove Ignition Coil and Spark Plug

1. Remove the engine cover if necessary.
2. Disconnect the electrical connector from the ignition coil of cylinder 1.
3. Unbolt the ignition coil and carefully pull it out.
4. Remove the spark plug using a spark plug socket and ratchet.

3. Inspect and Replace Components

1. Ignition Coil:
   • Inspect the ignition coil for cracks or corrosion. If damaged, replace it with a new OEM or high-quality aftermarket coil.
2. Spark Plug:
   • Check the spark plug for wear or fouling. If the electrode is worn or there are deposits, replace it with the recommended spark plug type (e.g., NGK or Bosch).
   • Torque the new spark plug to the manufacturer’s specification (usually around 23 Nm).

4. Test Fuel Injector and Reassemble

1. Use a multimeter to check the resistance of the fuel injector for cylinder 1; compare it to specifications.
2. If necessary, clean the fuel injector using a cleaning kit or replace it if defective.
3. Reinstall the ignition coil and secure it with bolts. Reconnect the electrical connector.
4. Reattach the engine cover if removed.

5. Final Checks

• Reconnect the negative battery terminal.
• Clear the fault codes using the OBD-II scanner.