how to fix BMW 3 Series G20/G21 (2019-2024) engine misfire P0301 code?

Solution

1. Preparation

• Gather necessary tools and parts.
• 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 needed)

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1 by unbolting it and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and inspect for wear or damage.
• If worn, replace with a new spark plug, ensuring it meets manufacturer specifications (e.g., gap size).
• Reinstall the ignition coil, ensuring it clicks into place, and reconnect the electrical connector.

3. Test and Replace Ignition Coil (if necessary)

• Use a multimeter to check the resistance of the ignition coil; compare with manufacturer specifications.
• If the coil is faulty, replace it with a new one.
• Reinstall the ignition coil and connect it properly.

4. Perform Compression Test

• Remove the spark plug from cylinder 1 and insert the compression tester.
• Crank the engine and record the compression reading.
• If the compression is low, further investigation into valve seating or piston rings may be required.

5. Inspect and Clean Fuel Injector

• Remove the fuel injector from cylinder 1.
• Clean the injector using a fuel injector cleaner kit to remove any blockages.
• Reinstall the fuel injector ensuring it is seated properly.