why does my Ford F-150's engine misfire when accelerating

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to avoid electrical shorts.

2. Replace Spark Plugs

• Remove the ignition coil(s) by unbolting them and disconnecting the electrical connectors.
• Use a spark plug socket to remove old spark plugs.
• Inspect the spark plug wires for damage; replace if necessary.
• Install new spark plugs, ensuring they are gapped correctly according to manufacturer specifications.
• Reinstall ignition coils and reconnect electrical connectors.

3. Inspect and Replace Ignition Coils (if needed)

• If misfire codes point to faulty ignition coils, remove them as described above.
• Install new ignition coils by reversing the removal process.
• Ensure all connections are secure.

4. Check and Repair Fuel System

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position (do not start the engine) to check fuel pressure readings.
• If pressure is low, inspect and replace the fuel filter and check the fuel pump operation.

5. Inspect for Vacuum Leaks

• Visually inspect all vacuum hoses and intake manifold for cracks or disconnections.
• Use a smoke machine or carburetor cleaner to identify leaks while the engine is running.
• Replace any damaged hoses or gaskets.