what does the P0302 code mean on my BMW 3 Series G20/G21 (2019-2024)?

Solution

1. Preparation

• Gather the required tools and parts.
• Disconnect the battery to ensure safety during repairs.
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if necessary.
  2. Locate and remove the spark plug for cylinder 2 using a spark plug socket.
  3. Inspect the spark plug for wear, fouling, or damage. Replace it if necessary.
  4. Use a torque wrench to install the new spark plug to the manufacturer’s specifications (typically around 18-22 lb-ft).

3. Check and Replace Ignition Coil

• Sub-steps:
  1. Disconnect the electrical connector from the ignition coil for cylinder 2.
  2. Remove the ignition coil by unscrewing it from the cylinder head.
  3. Inspect the coil for cracks or corrosion. Replace it if damaged.
  4. Install the new ignition coil and reconnect the electrical connector.

4. Inspect and Replace Fuel Injector

• Sub-steps:
  1. Disconnect the fuel line and electrical connector from the fuel injector for cylinder 2.
  2. Remove the fuel injector from the intake manifold.
  3. Inspect the injector for clogs or damage. If faulty, replace it with a new one.
  4. Ensure to apply fuel injector o-rings on installation to prevent leaks.

5. Perform Compression Test

• Sub-steps:
  1. Remove the spark plug for cylinder 2 again.
  2. Insert the compression gauge into the spark plug hole.
  3. Crank the engine a few times to get a reading; compare it to specifications (typically 120-150 psi).
  4. If compression is low, further inspection of piston rings or valves may be needed.