how to fix the P0302 cylinder 2 misfire in my BMW 3 Series F30/F31 (2012-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the electrical components.

2. Inspect and Replace Ignition Coil

• Tools Required: Socket set, torque wrench, anti-seize lubricant.
• Remove the engine cover if applicable.
• Disconnect the wiring harness from the ignition coil of cylinder 2.
• Remove the ignition coil using a socket wrench.
• Inspect the ignition coil for damage; replace with a new coil if necessary.
• Reinstall the ignition coil, applying anti-seize lubricant on the threads and tightening to manufacturer's specifications (typically around 10-15 Nm).
• Reconnect the wiring harness.

3. Inspect and Replace Spark Plug

• Tools Required: Spark plug socket, torque wrench, anti-seize lubricant.
• Remove the ignition coil again to access the spark plug.
• Use a spark plug socket to remove the spark plug from cylinder 2.
• Inspect the spark plug for wear or damage; replace if necessary.
• Install a new spark plug, applying anti-seize lubricant on the threads and tightening to the recommended torque (usually around 25-30 Nm).
• Reinstall the ignition coil.

4. Check and Replace Fuel Injector

• Tools Required: Fuel injector removal tool, torque wrench, shop rag.
• Disconnect the fuel injector connector for cylinder 2.
• Remove the fuel rail if necessary to access the injector.
• Use the fuel injector removal tool to carefully remove the fuel injector from cylinder 2.
• Inspect the injector for blockages or damage; replace if necessary.
• Install a new fuel injector, ensuring it is seated correctly and secured.
• Reconnect the fuel injector connector.

5. Perform Final Checks

• Reconnect the battery and clear any existing trouble codes with an OBD-II scanner.
• Start the engine and allow it to reach operating temperature.