how to diagnose P0301 misfire code in Ford Explorer Sixth Generation (2020-present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to prevent any electrical short circuits during repairs.

2. Inspect and Replace Spark Plug

• Sub-steps:
  1. Remove the engine cover if applicable using a socket set.
  2. Disconnect the ignition coil connector for cylinder 1.
  3. Remove the ignition coil using a socket set.
  4. Remove the spark plug using a spark plug socket.
  5. Inspect the spark plug for damage or excessive wear; replace if necessary with a new spark plug (OEM specifications: typically about 0.028-0.032 inches gap).
  6. Reinstall the new spark plug and torque it to the manufacturer’s specifications (usually around 13 lb-ft).

3. Inspect and Replace Ignition Coil

• Sub-steps:
  1. If the spark plug is fine, inspect the ignition coil for cracks or corrosion.
  2. Test the ignition coil with a multimeter to ensure proper resistance (refer to service manual for specifications).
  3. If faulty, replace the ignition coil with a new one using the manufacturer’s part number.
  4. Reconnect the ignition coil and reattach the electrical connector.

4. Inspect and Test Fuel Injector

• Sub-steps:
  1. Locate the fuel injector for cylinder 1 and disconnect its electrical connector.
  2. Using a noid light, check for proper signal to the fuel injector.
  3. If no signal is present, further diagnose the wiring or ECM.
  4. If the injector is faulty, replace it with an OEM part.
  5. Reconnect the injector and electrical connector.

5. Compression Test

• Sub-steps:
  1. Remove the spark plug for cylinder 1.
  2. Insert a compression gauge into the spark plug hole and crank the engine.
  3. Record the compression reading and compare it to manufacturer specifications (typically around 150-200 psi).
  4. If compression is low, investigate further for potential internal engine issues.