how to fix the P0302 code in my BMW 5 Series G30/G31 (2017-2024)

Solution

1. Preparation

• Gather necessary tools and parts.
• Tools Required: OBD-II scanner, socket set, torque wrench, compression tester, multimeter, fuel injector cleaner.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Replace Spark Plug

• Remove the engine cover (if applicable).
• Disconnect the ignition coil connector for cylinder 2.
• Use a socket wrench to remove the spark plug.
• Inspect the old spark plug for damage or fouling.
• Install the new spark plug, tightening it to the manufacturer's specified torque (usually around 20 Nm).
• Reconnect the ignition coil connector.

3. Replace Ignition Coil

• Disconnect the battery negative terminal.
• Remove the ignition coil for cylinder 2 by unbolting it and lifting it out.
• Install the new ignition coil, ensuring it is seated properly.
• Reconnect the battery terminal.

4. Test Fuel Injector

• Using a multimeter, check the resistance of the fuel injector for cylinder 2. It should match the specifications in the service manual (typically 12-16 ohms).
• If faulty, replace the fuel injector by removing it from the fuel rail and installing a new one. Ensure to replace any O-rings as well.

5. Perform Compression Test (if necessary)

• Remove the spark plug from cylinder 2.
• Install the compression tester into the spark plug hole.
• Crank the engine and record the compression reading. Compare it to the manufacturer's specified range (usually around 130-200 psi).
• If the compression is low, further investigation into valve or piston issues is required.