my BMW 5 Series F10/F11 is getting a P0303 code, what could be causing it

Solution

1. Preparation

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

2. Remove Ignition Components

• Remove the engine cover (if applicable):
  • Use a socket set to remove any bolts securing the cover.
• Remove the ignition coil for cylinder 3:
  • Disconnect the electrical connector from the ignition coil.
  • Remove the bolts securing the ignition coil and carefully pull the coil out.

3. Inspect and Replace Spark Plug

• Remove the spark plug for cylinder 3:
  • Use a spark plug socket to remove the spark plug after ensuring the area is clean to avoid debris entering the cylinder.
• Inspect the spark plug for wear, fouling, or damage. Replace if necessary.
• Install a new spark plug:
  • Use a torque wrench to tighten the spark plug to the manufacturer’s specifications (usually around 15-20 lb-ft).

4. Check and Replace Ignition Coil (if needed)

• Inspect the ignition coil for signs of damage or corrosion.
• If the ignition coil is faulty, replace it with a new one.
• Reinstall the ignition coil and reconnect the electrical connector.

5. Reassemble and Reconnect

• Reinstall the engine cover (if applicable) and secure it with bolts.
• Reconnect the negative battery terminal.