how to fix P0300 misfire code in Ford Mustang S650 (2024-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Spark Plugs

• Tools Required: Socket set, spark plug socket, torque wrench.
• Remove the ignition coil cover if applicable.
• Disconnect the ignition coils and remove them.
• Using a spark plug socket, carefully remove the spark plugs.
• Inspect each spark plug for wear; replace any that are worn or damaged.
• Install new spark plugs, ensuring they are gapped correctly (consult manufacturer specifications).
• Torque the spark plugs to the manufacturer’s specifications (typically around 13-15 lb-ft).

3. Check and Replace Ignition Coils

• Reconnect ignition coils to their respective positions.
• If any coils were found defective during inspection, replace them with new ones.
• Ensure the connectors are secure.

4. Fuel System Inspection

• Tools Required: Fuel pressure gauge.
• Connect the fuel pressure gauge to the fuel rail.
• Turn the ignition key to the "ON" position (do not start) to check for proper fuel pressure.
• If the pressure is below specifications, check the fuel pump and filter.
• Replace the fuel filter if clogged and consider replacing the fuel pump if necessary.

5. Inspect and Clean Fuel Injectors

• Remove the fuel injectors from the rail.
• Use a fuel injector cleaning kit to clean the injectors or replace them if they are faulty.
• Reinstall the cleaned or new injectors ensuring O-rings are lubricated and in good condition.

6. Inspect for Vacuum Leaks

• Inspect all vacuum hoses and the intake manifold for leaks.
• Replace any damaged hoses or gaskets.