how to solve my Ford F-150 12th Generation (2009-2014) with a P0302 misfire code

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, compression tester, fuel pressure gauge, basic hand tools.
• Ensure the vehicle is parked on a flat surface and the engine is off. Disconnect the battery for safety.

2. Replace Spark Plug

• Remove the engine cover if necessary.
• Disconnect the ignition coil connector for cylinder 2 and remove the ignition coil.
• Remove the spark plug using a spark plug socket.
• Inspect the old spark plug; if it is worn or fouled, replace it with a new spark plug (ensure it is the correct type and gap).
• Install the new spark plug and reattach the ignition coil and connector.

3. Test and Replace Ignition Coil

• If the spark plug replacement does not resolve the issue, test the ignition coil for cylinder 2.
• Use a multimeter to check the resistance; compare with manufacturer specifications.
• If the ignition coil is faulty, replace it with a new coil. Reconnect the ignition coil connector.

4. Inspect and Clean Fuel Injector

• If the ignition coil is functioning properly, check the fuel injector for cylinder 2.
• Disconnect the fuel injector connector and use a noid light to ensure the injector is receiving the proper signal.
• If the injector is not firing, replace it.
• If it is firing, consider cleaning the injector using a fuel injector cleaner.

5. Perform Compression Test

• If misfire persists, perform a compression test on cylinder 2.
• Remove the spark plug and insert the compression tester in the spark plug hole.
• Crank the engine and record the compression reading. Refer to manufacturer specifications for acceptable values.
• If compression is low, further investigation may be needed (e.g., valve seals, head gasket).