how to fix P0301 misfire code in my Ford F-150 12th Generation (2009-2014)

Solution

1. Preparation

• Gather tools: OBD-II scanner, spark plug socket, compression tester, multimeter, fuel pressure gauge, basic hand tools.
• Ensure the vehicle is parked on a flat surface, and the engine is cool.
• Disconnect the battery to avoid electrical shorts during work.

2. Inspect and Replace Spark Plug

• Remove the ignition coil from cylinder 1 by unscrewing the retaining bolts and disconnecting the electrical connector.
• Remove the spark plug using a spark plug socket and inspect it for damage or excessive wear. Replace if necessary.
• Install a new spark plug (check gap specification) and torque it to the manufacturer’s specification (typically 12-15 ft-lbs).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Check and Replace Ignition Coil

• If the spark plug looks good, test the ignition coil using a multimeter. Measure the primary and secondary resistance according to specifications.
• If the coil is faulty, remove it and replace it with a new one, ensuring it’s securely connected.

4. Fuel Injector Inspection

• If the issue persists, use a noid light to check for injector pulse. If there’s no pulse, inspect wiring and connections.
• If the injector is faulty, remove it and replace it with a new one, ensuring to clean the injector port.

5. Compression Test

• If misfire remains unresolved, perform a compression test on cylinder 1.
• If compression is low, further investigation into valve or piston issues may be required.