how to fix P0302 misfire code in BMW X3 G01 (2018-2024)

Solution

1. Preparation

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

Tools Required:

• OBD-II scanner
• Socket set
• Torque wrench
• Compression tester
• Multimeter
• Fuel injector cleaning kit (if necessary)

2. Replace Spark Plug

1. Remove the engine cover (if applicable) using a socket set.
2. Locate the spark plug for cylinder 2.
3. Use a spark plug socket to unscrew and remove the old spark plug.
4. Inspect the old spark plug for damage or wear patterns.
5. Install a new spark plug, ensuring it is gapped to the manufacturer's specifications (typically between 0.028-0.032 inches).
6. Torque the new spark plug to the specified value (usually around 20 Nm).

3. Check and Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil for cylinder 2.
2. Remove the ignition coil using a socket set.
3. Test the ignition coil with a multimeter to ensure it is functioning correctly (check resistance).
4. If faulty, replace it with a new ignition coil.
5. Reconnect the ignition coil and electrical connector.

4. Inspect and Clean Fuel Injector

1. Remove the fuel rail if necessary (consult repair manual for specifics).
2. Disconnect the fuel line and electrical connectors from the fuel injector for cylinder 2.
3. Remove the injector from the rail.
4. Clean the injector using a fuel injector cleaning kit.
5. Reinstall the cleaned or new injector, ensuring proper seating.

5. Perform Compression Test

1. Remove the spark plug for cylinder 2.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine for several seconds and record the compression reading.
4. Compare the reading with the manufacturer's specifications (usually around 140-200 psi).
5. If compression is low, further investigation into engine internals may be required.