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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, compression tester, vacuum gauge.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plug

1. Remove the engine cover, if applicable.
2. Use a socket wrench to remove the spark plug from cylinder 2.
3. Inspect the old spark plug for signs of wear or fouling.
4. Install a new spark plug (OEM specifications recommended).
5. Torque the new spark plug to the manufacturer's specified value (typically around 20 Nm).

3. Test and Replace Ignition Coil (if necessary)

1. Disconnect the wiring harness from the ignition coil for cylinder 2.
2. Remove the ignition coil using a socket wrench.
3. Measure the resistance of the ignition coil with a multimeter (typically should be between 0.5-1.5 ohms).
4. If the resistance is out of spec, install a new ignition coil.
5. Reconnect the wiring harness and ensure it clicks into place.

4. Inspect and Test Fuel Injector

1. Remove the fuel rail cover, if applicable.
2. Disconnect the fuel injector connector for cylinder 2.
3. Use a noid light to check for proper electrical signal to the injector.
4. If no signal is present, trace the wiring or replace the injector if it is faulty.
5. If the injector is functioning, reassemble all components.

5. Perform Compression Test (if necessary)

1. Remove the spark plug for cylinder 2.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine a few times to obtain a reading.
4. Compare the reading with the manufacturer’s specifications (typically around 130-200 psi). If low, further engine diagnostics may be needed.