how to fix P0300 misfire code in Ford F-150 Fourteenth Generation (2021-present)

Learn how to diagnose and fix P0300 random/multiple cylinder misfire in Ford F-150. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to avoid electrical shorts.
• Allow the engine to cool before beginning work.

2. Inspect and Replace Spark Plugs

• Remove the ignition coils from the spark plugs by unhooking the electrical connectors and unscrewing the bolts.
• Carefully pull out the spark plugs using a spark plug socket.
• Inspect the spark plugs for wear, carbon buildup, or damage. Replace if necessary.
• Install new spark plugs to the manufacturer's specifications (typically 13-15 lb-ft torque).

3. Check and Replace Ignition Coils

• If spark plugs are in good condition, test the ignition coils for functionality using a multimeter.
• Replace any faulty ignition coils with new ones. Ensure proper seating and connection.
• Reinstall all components in reverse order.

4. Fuel System Inspection and Repair

• If the fuel pressure was low in the diagnostic step, check the fuel filter for clogs and replace if necessary.
• Verify the operation of the fuel injectors by testing their resistance and replacing any that are faulty.
• Ensure the fuel lines are free of leaks and obstructions.

5. Vacuum Leak Inspection

• Inspect all vacuum hoses and connections for cracks or disconnections. Replace any damaged hoses.
• Use a smoke machine or carburetor cleaner to identify any vacuum leaks during idle.

6. Compression Testing

• If compression results show low pressure in any cylinders, consider further investigation into the engine's internal components (valves, piston rings, etc.).
• Address any internal engine issues as needed.