how do I fix a P0304 code on my Ford F-150 13th Generation (2015-2020)

Learn how to diagnose and fix P0304 cylinder 4 misfire in Ford F-150 (2015-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts for the repair.
• Disconnect the battery to prevent electrical shock.
• Allow the engine to cool before starting work.

2. Replace Spark Plug and Ignition Coil

1. Remove Engine Covers (if applicable)
   • Use a socket set to remove any screws or bolts.
2. Access Cylinder 4
   • Identify and locate cylinder 4 based on the engine layout (typically the second cylinder on the left bank for V6/V8 engines).
3. Remove the Ignition Coil
   • Unplug the electrical connector from the ignition coil.
   • Remove the bolts securing the ignition coil using a socket set.
   • Pull the ignition coil out of the spark plug well.
4. Replace the Spark Plug
   • Use a spark plug socket to remove the spark plug from cylinder 4.
   • Inspect the old spark plug for signs of wear or fouling.
   • Install a new spark plug, ensuring it is gapped correctly (consult specifications).
   • Torque the spark plug to the manufacturer’s specification (typically around 13-15 lb-ft).
5. Install New Ignition Coil
   • Place the new ignition coil onto the spark plug and secure it with bolts.
   • Reconnect the electrical connector to the ignition coil.

3. Check for Vacuum Leaks

1. Inspect Hoses and Connections
   • Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
   • Use a smoke machine or carburetor cleaner to detect leaks by spraying around suspected areas.
2. Repair or Replace Affected Hoses
   • Replace any damaged hoses with OEM or high-quality aftermarket parts.

4. Fuel Injector Cleaning/Replacement

1. Test the Fuel Injector
   • Use a multimeter to check the resistance of the fuel injector.
   • If defective, remove the fuel rail and replace the faulty injector.
2. Reinstall Fuel Rail
   • Follow the manufacturer’s guidelines for torque specifications when reinstalling the fuel rail.