what causes P0301 code on my BMW 3 Series F30/F31 (2012-2019)?

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Replace Spark Plug

1. Remove the engine cover (if applicable) to access the ignition components.
2. Use a spark plug socket and ratchet to remove the spark plug from cylinder 1.
3. Inspect the spark plug condition; replace if worn or fouled.
4. Apply anti-seize lubricant to the threads of the new spark plug.
5. Install the new spark plug and torque it to the manufacturer’s specifications (usually around 15-20 ft-lbs).
6. Reinstall the engine cover.

3. Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil for cylinder 1.
2. Remove the mounting bolts securing the ignition coil.
3. Pull the ignition coil out of the spark plug tube.
4. Install the new ignition coil and secure it with the mounting bolts.
5. Reconnect the electrical connector.

4. Inspect and Clean Fuel Injector

1. Remove the fuel rail (if necessary to access the injector) following the manufacturer's procedure.
2. Disconnect the fuel injector electrical connector.
3. Remove the fuel injector from the rail, inspecting for clogs or damage.
4. Clean the injector using a fuel injector cleaner or replace it if necessary.
5. Reinstall the injector, ensuring it is seated properly in the rail.

5. Conduct Compression Test

1. Remove the spark plug from cylinder 1.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine for a few seconds and record the pressure reading.
4. Compare the reading to manufacturer specifications; replace if significantly low.

Tools Required:

• OBD-II scanner
• Spark plug socket
• Ratchet and extension
• Torque wrench
• Ignition coil puller (optional)
• Compression tester
• Fuel injector cleaning kit

Parts Required:

• Spark plug (for cylinder 1)
• Ignition coil (for cylinder 1)
• Fuel injector (if necessary)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical systems.
• Allow the engine to cool before performing any repairs.