why is my BMW X3 G01 (2018-2024) engine misfiring when idling

Solution

1. Preparation

• Gather tools and materials.
• Ensure the engine is cool and the vehicle is parked on a level surface.
• Disconnect the negative terminal of the battery to prevent electrical shorts.

2. Inspect and Replace Spark Plugs

• Sub-steps:
  1. Remove the engine cover if necessary.
  2. Disconnect the ignition coils from the spark plugs.
  3. Use a spark plug socket to carefully remove the spark plugs.
  4. Inspect each spark plug for wear or carbon buildup; replace with OEM plugs if needed.
  5. Gap the new spark plugs according to manufacturer specifications (typically 0.032-0.036 inches for BMW).
  6. Reinstall the spark plugs and reconnect the ignition coils.

3. Check and Replace Ignition Coils

• Sub-steps:
  1. With the ignition coils accessible, remove them from the spark plugs.
  2. Test each ignition coil with a multimeter for resistance; replace any coils outside of specifications.
  3. Install new ignition coils ensuring they are seated properly on the spark plugs.

4. Inspect Fuel Injectors

• Sub-steps:
  1. Remove any components obstructing access to the fuel rail.
  2. Disconnect the fuel injector connectors and remove the fuel rail.
  3. Inspect each fuel injector for clogs or leaks; clean or replace as necessary.
  4. Reinstall the fuel rail and reconnect the injectors.

5. Test Fuel Pressure

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition on without starting the engine to check the pressure. It should typically be around 50-70 psi (check specifications).
  3. If pressure is low, check the fuel pump and fuel filter for issues.