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

Solution

1. Preparation

• Gather necessary tools and materials.
• Disconnect the vehicle's battery (negative terminal).
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench.
• Remove the ignition coil cover if applicable.
• Using the socket set, remove the spark plug from cylinder 1.
• Inspect the spark plug for wear, carbon buildup, or damage; replace if necessary.
• Install the new spark plug and torque it to the manufacturer’s specification (typically around 18-22 lb-ft).

3. Inspect and Replace Ignition Coil

• Tools Required: Socket set.
• Remove the ignition coil from cylinder 1 by unscrewing any retaining bolts.
• Inspect the ignition coil for cracks or damage; replace if necessary.
• Install the new ignition coil and ensure it is securely fastened.

4. Test and Replace Fuel Injector (if necessary)

• Tools Required: Fuel injector tester or noid light.
• Disconnect the electrical connector from the fuel injector of cylinder 1.
• Use a fuel injector tester or noid light to check for proper operation.
• If the injector is faulty, remove it using pliers and a socket set, and replace it with a new injector.

5. Check Compression

• Tools Required: Compression tester.
• Remove the spark plug again for cylinder 1.
• Insert the compression tester into the spark plug hole and crank the engine.
• Record the compression reading; it should be within the manufacturer’s specifications (typically around 150-200 psi). If it is low, further investigation is required for potential valve or head gasket issues.

6. Reassemble and Clear Codes

• Reinstall the spark plug, ignition coil, and any covers removed during the process.
• Reconnect the battery.
• Use the OBD-II scanner to clear the P0301 code and any other stored codes.