how to fix P0301 misfire code on my Ford F-150 Fourteenth Generation (2021-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the ignition coil from cylinder 1 by unscrewing the retaining bolts and disconnecting the electrical connector.
  2. Remove the spark plug using a spark plug socket and ratchet.
  3. Inspect the spark plug for wear, carbon deposits, or damage; replace if necessary with the manufacturer's specified part (usually Motorcraft SP-534).
  4. Install the new spark plug, ensuring it’s torqued to the manufacturer's specifications (typically around 13 lb-ft).
  5. Reconnect the ignition coil and secure it with the retaining bolts.

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug is in good condition, test the ignition coil using a multimeter to check for proper primary and secondary resistance.
  2. If the coil is faulty, remove it and install a new ignition coil compatible with the F-150 (Motorcraft DG-511).
  3. Reconnect the electrical connector and ensure it is secured properly.

4. Test Fuel Injector

• Sub-steps:
  1. Disconnect the fuel injector connector for cylinder 1.
  2. Use a noid light to check for signal; if there is no signal, further diagnose the wiring or engine control module.
  3. If the fuel injector is faulty, remove it using a fuel injector puller, and replace it with a new one (Motorcraft CM-5220).
  4. Ensure all connectors are securely reattached.

5. Compression Test (if necessary)

• Sub-steps:
  1. Remove the spark plug from cylinder 1.
  2. Install a compression gauge into the spark plug hole.
  3. Crank the engine several times and record the reading; it should be within manufacturer specifications (around 120-200 psi).
  4. If compression is low, further investigate potential internal engine issues.