how to fix P0301 code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety.
• Allow the engine to cool before working on any components.

2. Replace Spark Plug

• Remove the engine cover if applicable using a socket set.
• Remove the ignition coil from cylinder 1 by unscrewing the retaining bolts and disconnecting the electrical connector.
• Extract the spark plug from cylinder 1 using a spark plug socket.
• Inspect the spark plug for damage; if worn, replace it with a new spark plug that meets OEM specifications (e.g., NGK or Bosch).
• Torque the new spark plug to the manufacturer's specifications (typically around 20 Nm).
• Reinstall the ignition coil and engine cover.

3. Check and Replace Ignition Coil (if necessary)

• If the ignition coil appears damaged or is not functioning, replace it.
• Disconnect the electrical connector and remove the retaining bolts for the ignition coil.
• Install the new ignition coil and reconnect the electrical connector.
• Ensure it is seated properly and secure.

4. Inspect Fuel Injector (if necessary)

• If misfire persists, test the fuel injector for cylinder 1.
• Disconnect the fuel injector connector and use a multimeter to check for resistance.
• If the injector is faulty, replace it by removing the fuel rail if necessary, and install a new injector.
• Ensure proper sealing and reconnect all hoses and electrical connections.

5. Compression Test (if misfire remains)

• If the previous steps do not resolve the issue, perform a compression test on cylinder 1.
• Remove the spark plug and insert a compression tester into the spark plug hole.
• Crank the engine and read the compression value; compare it against manufacturer specifications.
• If compression is low, further investigation into internal engine components may be necessary.

Tools Required:

• OBD-II scanner
• Socket set
• Spark plug socket
• Torque wrench
• Multimeter
• Compression tester

Parts Required:

• Spark plug
• Ignition coil (if needed)
• Fuel injector (if needed)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical systems.
• Allow the engine to cool before opening any components.