my BMW 3 Series F30/F31 (2012-2019) has a check engine light and a P0301 code

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the battery (negative terminal) to ensure safety while working on electrical components.

2. Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover (if applicable) using a socket set.
  2. Locate the spark plug in cylinder 1.
  3. Use a spark plug socket to remove the old spark plug.
  4. Inspect the old spark plug for wear; replace if necessary.
  5. Install the new spark plug, tightening to the manufacturer's specified torque (usually around 18-22 ft-lbs).

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. Disconnect the electrical connector from the ignition coil.
  2. Remove the ignition coil from cylinder 1 using a socket set.
  3. Install the new ignition coil, ensuring it is seated properly.
  4. Reconnect the electrical connector.

4. Check Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Use a fuel injector tester to ensure it is functioning correctly.
  3. Replace the fuel injector if it is found to be faulty, ensuring proper seating and connection.

5. Perform Compression Test

• Sub-steps:
  1. Remove the spark plug for cylinder 1 to access the combustion chamber.
  2. Insert the compression tester into the spark plug hole.
  3. Crank the engine to get a reading; compare the results with manufacturer specifications.
  4. Address any compression issues if readings are low (indicating potential internal engine problems).