how to diagnose a misfire in my Ford Explorer Fifth Generation (2011-2019)

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, fuel pressure gauge, multimeter.
• Disconnect the battery before starting the repair to ensure safety.

2. Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket set.
2. Disconnect the ignition coils from the spark plugs.
3. Use a spark plug socket to remove the old spark plugs.
4. Inspect the spark plugs for wear; replace with OEM specifications (usually Motorcraft SP-534).
5. Install new spark plugs, torquing them to the manufacturer’s specifications (typically 13 lb-ft).
6. Reconnect the ignition coils.

3. Replace Ignition Coils (if necessary)

1. Disconnect the battery again for safety.
2. Remove the bolts securing the ignition coils using a socket set.
3. Lift the ignition coils off the spark plugs.
4. Install new ignition coils (OEM recommended).
5. Reattach the bolts and reconnect the electrical connectors.

4. Check and Replace Fuel System Components

1. Connect the fuel pressure gauge to the fuel rail.
2. Turn the ignition on (do not start the engine) to check fuel pressure (should be within manufacturer's specifications).
3. If pressure is low, replace the fuel filter and check the fuel pump.
4. If necessary, replace the fuel injectors using proper procedures for access.

5. Inspect and Repair Vacuum Leaks

1. Visually inspect all vacuum hoses and connections for cracks or disconnections.
2. Use a smoke machine or carburetor cleaner to identify any vacuum leaks by spraying around the intake manifold and hoses.
3. Replace or repair any damaged hoses.