how to fix P0303 code on Ford F-150 13th Generation (2015-2020)

Learn how to diagnose and fix P0303 cylinder 3 misfire in Ford F-150 (2015-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts, ensuring the vehicle is parked on a level surface.
• Disconnect the battery to prevent electrical shorts.
• Allow the engine to cool completely before proceeding.

2. Replace Spark Plug

• Sub-steps:
  1. Remove the ignition coil from cylinder 3 by unscrewing the bolts and disconnecting the electrical connector.
  2. Extract the spark plug using a spark plug socket and ratchet. Inspect the old spark plug for damage or excessive wear.
  3. Install a new spark plug, ensuring it is gapped to the manufacturer’s specification.
  4. Reinstall the ignition coil over the new spark plug and reconnect the electrical connector.

3. Replace Ignition Coil (if necessary)

• Sub-steps:
  1. If the ignition coil tested out of specification, remove the coil as previously stated.
  2. Install the new ignition coil and secure it with bolts.
  3. Reconnect the electrical connector.

4. Inspect and Replace Fuel Injector (if necessary)

• Sub-steps:
  1. Disconnect the fuel rail and remove the fuel injector for cylinder 3.
  2. Inspect the injector for clogs or damage. Test its resistance using a multimeter.
  3. Install a new fuel injector if the old one is faulty, ensuring it is seated correctly in the fuel rail.

5. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the battery terminals securely.
  2. Use the OBD-II scanner to clear the P0303 code and any other stored codes.

Tools Required:

• OBD-II scanner
• Spark plug socket
• Ratchet and socket set
• Multimeter
• Fuel pressure gauge
• Noid light (optional)

Parts Required:

• Spark plug (for cylinder 3)
• Ignition coil (if needed)
• Fuel injector (if needed)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical components.
• Allow the engine to cool before opening the hood to prevent burns.