what does error code P0302 mean for my BMW 3 Series E90/E91 (2005-2012)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Replace Spark Plug

• Remove the engine cover if applicable.
• Locate cylinder 2 spark plug (usually the second spark plug from the left when facing the engine).
• Using a socket wrench, remove the spark plug.
• Inspect the spark plug for signs of wear (e.g., fouling, damage).
• Install a new spark plug, ensuring the gap is set to manufacturer specifications (typically around 0.030-0.035 inches).
• Torque the spark plug to the manufacturer's specifications (usually around 15-20 ft-lbs).

3. Replace Ignition Coil

• Disconnect the wiring harness from the ignition coil located on cylinder 2.
• Remove the ignition coil by pulling it straight out of the spark plug well.
• Install a new ignition coil and ensure it is seated properly.
• Reconnect the wiring harness.

4. Inspect and Clean Fuel Injector

• Remove the fuel rail to gain access to the fuel injector for cylinder 2.
• Carefully disconnect the fuel line (use a rag to catch any spills).
• Remove the fuel injector from the rail.
• Inspect the fuel injector for clogs; clean or replace if necessary.
• Reinstall the fuel injector and ensure proper seating.

5. Reassemble and Test

• Reattach the fuel line and fuel rail.
• Reconnect the battery.
• Start the engine and monitor for any abnormal sounds or issues.
• Check for any new error codes using the OBD-II scanner.