how to fix P0302 misfire code on Ford F-150 12th Generation (2009-2014)

Solution

1. Preparation

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

2. Inspect and Replace Spark Plug

• Tools Required: Socket set, torque wrench, dielectric grease.
• Remove the ignition coil from cylinder 2:
  • Disconnect the electrical connector.
  • Remove the mounting bolts and gently pull the coil out.
• Remove the spark plug using a spark plug socket:
  • Inspect the spark plug for wear; replace if fouled or worn.
  • Torque the new spark plug to the manufacturer’s specification (typically 13-15 lb-ft).
• Apply dielectric grease to the inside of the ignition coil boot before reinstallation.

3. Check and Replace Ignition Coil

• If the spark plug is good, test the ignition coil:
  • Swap the ignition coil with one from a different cylinder if possible.
  • Clear the error codes and test drive the vehicle to see if the misfire follows the coil.
• If needed, replace the ignition coil for cylinder 2 with a new one, ensuring proper seating and connection.

4. Inspect and Replace Fuel Injector

• If misfire persists, check the fuel injector:
  • Disconnect the fuel injector electrical connector.
  • Remove the injector with a fuel injector puller if necessary.
• Inspect the injector for clogs or damage; clean or replace as needed.
• Reinstall the injector and reconnect the electrical connector.

5. Final Assembly and Testing

• Reinstall any components that were removed during the inspection.
• Reconnect the negative battery terminal.
• Start the engine and monitor for any misfire symptoms.
• Use the OBD-II scanner to check for codes again; ensure P0302 is resolved.