how to fix P0301 misfire code on my Ford Mustang S550 (2015-2023)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to avoid electrical short circuits.

Tools Required:

• OBD-II scanner
• Socket set
• Torque wrench
• Compression tester
• Multimeter

2. Inspect and Replace Spark Plug

• Remove the ignition coil for cylinder 1:
  • Disconnect the electrical connector.
  • Remove the retaining bolts and pull the coil out.
• Remove the spark plug:
  • Use a spark plug socket to unscrew the spark plug from the cylinder head.
• Inspect the spark plug:
  • Check for wear, fouling, or damage. Replace if necessary.
• Install a new spark plug:
  • Torque to manufacturer's specifications (typically around 12-15 lb-ft).

3. Inspect and Replace Ignition Coil

• If the spark plug is in good condition, test the ignition coil:
  • Use a multimeter to check the coil’s resistance (should be within manufacturer specifications).
• Replace the ignition coil if it is faulty:
  • Install the new coil, ensuring it seats properly.
  • Reconnect the electrical connector and secure with bolts.

4. Clean or Replace Fuel Injector

• If the ignition components are functioning correctly, check the fuel injector:
  • Remove the fuel injector from cylinder 1.
  • Clean it using an ultrasonic cleaner or replace it with a new one.
• Reinstall the injector and reconnect the fuel line.

5. Check Compression

• If issues persist, perform a compression test:
  • Remove the spark plug and insert the compression tester.
  • Crank the engine and record the compression reading.
• Compare the reading with manufacturer specifications. Replace the cylinder head gasket or repair internal engine issues if compression is low.