how to diagnose P0301 code in Ford F-150 14th Generation (2021-2024)

Solution

1. Preparation

• Gather tools and parts: OBD-II scanner, socket set, spark plug socket, compression tester, multimeter, fuel injector cleaner, torque wrench.
• Ensure the vehicle is parked on a level surface and the engine is cool.

2. Replace Spark Plug

1. Disconnect the negative battery terminal to avoid electrical shorts.
2. Remove the engine cover if applicable.
3. Locate the spark plug for cylinder 1 (usually at the front of the engine).
4. Use a spark plug socket to remove the old spark plug.
5. Inspect the spark plug for signs of wear or damage.
6. Install a new spark plug, setting the gap to the manufacturer's specification (check owner’s manual).
7. Torque the spark plug to the specified value (typically around 13-15 lb-ft).

3. Test and Replace Ignition Coil

1. Disconnect the electrical connector from the ignition coil of cylinder 1.
2. Remove the ignition coil using a socket set.
3. Use a multimeter to test the primary and secondary resistance of the ignition coil (check specifications in the service manual).
4. If the coil is faulty, replace it with a new one.
5. Reinstall the ignition coil and reconnect the electrical connector.

4. Test Fuel Injector

1. Disconnect the fuel injector connector for cylinder 1.
2. Use a multimeter to check the resistance of the injector (should be within the manufacturer’s specifications).
3. If the injector is faulty, replace it.
4. Clean the fuel injector with a suitable injector cleaner (if applicable) before reinstallation.
5. Reconnect the fuel injector connector.

5. Compression Test

1. Remove the spark plug for cylinder 1.
2. Insert the compression tester into the spark plug hole.
3. Crank the engine several times to get a reading.
4. Compare the compression reading to the manufacturer's specifications (typically between 120-150 psi).
5. If compression is low, further investigation such as valve inspection or piston ring replacement may be required.