my Ford Mustang S650 (2024-Present) has a check engine light with code P0300

Solution

1. Preparation

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

2. Inspect and Replace Spark Plugs

1. Remove the engine cover if applicable.
2. Use a socket set to remove the spark plug wires or ignition coil connectors.
3. Remove the spark plugs using a spark plug socket.
4. Inspect the old spark plugs for wear and replace them with new ones if necessary.
   • Torque new spark plugs to the manufacturer’s specification (typically around 13-15 lb-ft).
5. Reinstall the spark plug wires or ignition coils.

3. Check and Replace Ignition Coils

1. If ignition coils are faulty, remove the bolts securing each coil using a socket set.
2. Disconnect the electrical connector from the ignition coil.
3. Replace the faulty ignition coil with a new one.
4. Reconnect the electrical connector and secure the coil back in place.

4. Inspect and Clean Fuel Injectors

1. Use a fuel injector cleaning kit or remove the fuel injectors for cleaning.
2. If cleaning off the vehicle, soak injectors in a cleaning solution and use compressed air to clean them.
3. Reinstall cleaned or new fuel injectors, ensuring proper seating to prevent leaks.

5. Repair Vacuum Leaks

1. Inspect all vacuum hoses for cracks or disconnections.
2. Replace any damaged hoses with new ones.
3. Use a smoke machine or carburetor cleaner to test for leaks around the intake manifold.