how do I fix P0302 misfire code on my BMW X5 F15 (2014-2019)?

Solution

1. Preparation

• Gather tools and ensure the vehicle is parked on a level surface with the engine cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug

• Remove the ignition coil for cylinder 2 by unscrewing the retaining bolts.
• Disconnect the electrical connector from the ignition coil.
• Remove the spark plug using a spark plug socket and ratchet.
• Inspect the old spark plug; if it shows signs of wear or fouling, replace it with a new spark plug that meets OEM specifications (e.g., NGK or Bosch).
• Install the new spark plug and torque it to the manufacturer's specifications (typically around 18-22 lb-ft).
• Reattach the ignition coil and connect the electrical connector.

3. Inspect and Replace Ignition Coil (if necessary)

• If the ignition coil appears damaged or if replacing the spark plug does not resolve the issue, replace the ignition coil for cylinder 2.
• Remove the old ignition coil and install the new one, ensuring it is seated properly.
• Connect the electrical connector securely.

4. Check Fuel Injector

• If the issue persists, inspect the fuel injector for cylinder 2.
• Remove the fuel injector connector and use a noid light to check for signal. If there's no signal, further investigation into the wiring may be necessary.
• If the injector is faulty, replace it with a new one, ensuring to replace any O-rings to prevent fuel leaks.

5. Reassemble and Clear Codes

• Reconnect the negative battery terminal.
• Use an OBD-II scanner to clear the P0302 code.
• Start the engine and allow it to idle to check for any misfires.