how to fix the P0301 code in my BMW 3 Series F30/F31 (2012-2019)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative terminal of the battery to ensure safety during the procedure.

2. Inspect and Replace Spark Plug

1. Remove the engine cover if applicable.
2. Remove the ignition coil from cylinder 1:
   • Unscrew the mounting bolt(s) using a socket wrench.
   • Gently pull the ignition coil out.
3. Remove the spark plug using a spark plug socket and ratchet:
   • Turn counterclockwise to loosen and remove.
4. Inspect the spark plug:
   • Look for signs of wear, fouling, or improper gap. Replace if necessary.
5. Install a new spark plug:
   • Set the gap according to the manufacturer specifications (usually around 0.030 inches).
   • Screw in the new spark plug by hand, then tighten with a torque wrench to the manufacturer’s torque specification (typically around 15 lb-ft).

3. Check and Replace Ignition Coil

1. If the ignition coil appears damaged, replace it:
   • Install the new ignition coil onto the spark plug, ensuring it is seated properly.
   • Secure it with the mounting bolt(s).
2. Reconnect the electrical connector to the ignition coil.

4. Inspect and Replace Fuel Injector (if needed)

1. If the injector is suspected of malfunction:
   • Disconnect the fuel injector connector.
   • Remove the fuel rail (if necessary) to access the injector.
2. Remove the old fuel injector:
   • Use a fuel injector puller if available.
3. Install a new fuel injector:
   • Lubricate the O-ring with engine oil for a proper seal.
   • Insert and secure it in place, reattaching the fuel rail if it was removed.

5. Final Steps

1. Reconnect the negative battery terminal.
2. Start the engine and allow it to idle for a few minutes to ensure proper operation.