how to fix P0174 code in Ford F-150 12th Generation (2009-2014)

Solution

1. Preparation

• Gather tools including an OBD-II scanner, fuel pressure gauge, multimeter, socket set, and cleaning supplies.
• Disconnect the vehicle battery to ensure safety.

2. Inspect Air Intake System

• Sub-steps:
  1. Remove the air intake duct by loosening the clamps and disconnecting any sensors attached.
  2. Visually inspect the duct for cracks or broken connections.
  3. Check the air filter and replace it if dirty.
  4. Reinstall the intake duct securely.

3. Check and Clean MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor in the air intake system.
  2. Disconnect the electrical connector from the MAF sensor.
  3. Remove the sensor using the appropriate socket size.
  4. Use MAF cleaner to spray the sensor gently and let it dry.
  5. Reinstall the sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Sub-steps:
  1. Locate the fuel rail on the engine.
  2. Connect the fuel pressure gauge to the test port on the fuel rail.
  3. Turn the ignition to the ON position without starting the engine and observe the pressure reading.
  4. Compare the reading to the manufacturer's specifications (typically between 30-45 psi). If it’s low, check the fuel pump and filter.

5. Inspect for Vacuum Leaks

• Sub-steps:
  1. Start the engine and listen for any hissing sounds indicating a vacuum leak.
  2. Use a smoke machine to introduce smoke into the intake system; look for escaping smoke which indicates a leak.
  3. If a leak is found, replace the damaged vacuum line or gasket.

6. Check Fuel Injectors

• Sub-steps:
  1. Disconnect the fuel injector wiring harness.
  2. Use a multimeter to check the resistance of each injector according to factory specifications.
  3. If an injector is faulty, remove it and replace it with a new one.