my Ford F-150 12th Generation (2009-2014) has a rough idle when warm what should I do

Solution

1. Preparation

• Gather necessary tools and parts. Ensure the vehicle is parked on a flat surface and the engine is off.
• Tools Required: OBD-II scanner, socket set, torque wrench, vacuum gauge, fuel pressure gauge, cleaning supplies.

2. Check and Replace Spark Plugs

• Remove the engine cover if applicable.
• Use a socket set to carefully remove the spark plug wires or coils.
• Remove the spark plugs using a spark plug socket and inspect for wear or deposits.
  • If they are worn or fouled, replace them with new spark plugs of the manufacturer's specification.
• Reinstall spark plugs, torque to manufacturer specifications (typically around 12-15 ft-lbs).
• Reconnect the spark plug wires or coils.

3. Clean Throttle Body

• Disconnect the negative battery terminal.
• Remove the air intake ducting from the throttle body using a socket set.
• Spray throttle body cleaner into the throttle body while manually opening the throttle plate.
• Wipe the interior with a clean cloth to remove carbon buildup.
• Reinstall the air intake ducting and reconnect the battery terminal.

4. Inspect and Repair Vacuum Leaks

• Use a vacuum gauge to check the engine vacuum at idle; normal readings are typically between 17-22 inHg.
• Inspect hoses and gaskets for cracks or leaks.
• Replace any damaged hoses or gaskets found during inspection.

5. Test Fuel System

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position without starting the engine to check the fuel pressure.
• If pressure is below manufacturer specifications (typically around 30-50 psi), inspect the fuel pump and filter for issues.
• Replace the fuel filter if it is clogged, and consider replacing the fuel pump if necessary.