what causes the engine to misfire in BMW 5 Series G30/G31 (2017-2024) with code P0301

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure safety while working on electrical components.

Tools Required:

• OBD-II scanner
• Socket set
• Torque wrench
• Compression tester
• Multimeter
• Noid light

2. Replace Ignition Coil

1. Remove the engine cover if applicable.
2. Disconnect the electrical connector from the ignition coil for cylinder 1.
3. Unbolt the ignition coil using the appropriate socket and remove it from the cylinder head.
4. Install the new ignition coil into cylinder 1 and tighten it to manufacturer specifications (typically around 10-12 Nm).
5. Reconnect the electrical connector to the ignition coil.

3. Replace Spark Plug

1. Use a spark plug socket to remove the spark plug from cylinder 1.
2. Inspect the spark plug for signs of wear or damage; replace if necessary.
3. Gap the new spark plug to manufacturer specifications (usually around 0.7-0.8 mm).
4. Install the new spark plug and tighten it to the specified torque (typically around 25 Nm).

4. Inspect and Replace Fuel Injector (if necessary)

1. Disconnect the fuel line and the electrical connector for the fuel injector.
2. Remove the fuel injector retaining clips and pull the injector out of the rail.
3. Inspect the old injector for clogs or leaks; replace if necessary.
4. Lubricate the O-rings of the new injector with clean engine oil and insert it into the rail.
5. Reinstall the retaining clips and reconnect the fuel line and electrical connector.

5. Check for Vacuum Leaks

1. Inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
2. Use a smoke machine or spray soapy water around joints and connections to identify leaks.
3. Replace damaged hoses and ensure all connections are secure.