my BMW X3 G01 (2018-2024) has a P0301 code; how do I fix it?

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, compression tester, multimeter.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool before starting work.

2. Inspect and Replace Ignition Coil

• Remove the engine cover if necessary to access the ignition coil.
• Disconnect the electrical connector from the ignition coil.
• Remove the bolt securing the ignition coil and carefully pull it out.
• Install the new ignition coil, ensuring it is seated properly.
• Reconnect the electrical connector and secure it with the bolt.

3. Check and Replace Spark Plug

• Remove the ignition coil again to access the spark plug.
• Using a spark plug socket, carefully unscrew and remove the spark plug.
• Inspect the spark plug for wear, carbon deposits, or damage.
• If necessary, replace with a new spark plug, ensuring the gap is set according to manufacturer specifications.
• Reinstall the spark plug and torque to the specified value (usually around 12-15 ft-lbs).

4. Perform Compression Test

• Remove the spark plug from cylinder 1 (if not already removed).
• Insert the compression tester into the spark plug hole.
• Crank the engine to get a compression reading; compare with specifications (typically 150-200 psi).
• If compression is low, further investigation of internal engine components may be required.

5. Inspect Fuel Injector

• Access the fuel rail to check the injector for cylinder 1.
• Disconnect the electrical connector from the fuel injector.
• Use a multimeter to test the injector's resistance; if it’s out of range, replace the injector.
• If the injector is clogged, consider cleaning it or replacing it.