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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, multimeter, fuel pressure gauge, vacuum gauge.
• Disconnect the negative battery terminal to avoid electrical shorts.
• Allow the engine to cool before working on any components.

2. Inspect and Replace Spark Plugs

• Remove the ignition coil cover if applicable.
• Using a socket wrench, carefully remove the spark plugs.
• Inspect each spark plug for signs of wear, carbon buildup, or oil fouling. Replace with OEM spark plugs if necessary.
• Ensure each spark plug is gapped to manufacturer specifications (typically 0.028-0.032 inches for Mustangs).
• Reinstall the spark plugs and torque to the specified value (typically around 12-15 lb-ft).

3. Check and Replace Ignition Coils

• Disconnect the electrical connectors from the ignition coils.
• Remove the ignition coils using a socket set.
• Inspect for physical damage; replace any faulty coils with OEM parts.
• Reinstall the ignition coils and ensure they are properly seated.

4. Fuel System Inspection

• Connect a fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the "On" position (do not start) to check fuel pressure.
• Verify that fuel pressure is within specification (typically around 30-50 psi for Mustangs).
• If pressure is low, check the fuel pump and filter; replace as necessary.

5. Vacuum Leak Check

• Use a vacuum gauge to assess the engine vacuum.
• Listen for hissing sounds around vacuum hoses and connections.
• If a leak is detected, replace any damaged hoses or reconnect loose fittings.

6. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0300 code.
• Start the engine and monitor for any reoccurrence of the code.