how to fix P0174 code in Honda Civic 9th Generation (2012-2015)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool completely before starting work.

2. Inspect for Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to detect leaks; spray around suspected areas and check for engine response changes.
• Tools Required: Smoke machine, carburetor cleaner, flashlight.

3. Clean or Replace MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the intake duct.
  • Disconnect the electrical connector and remove the sensor from the housing.
  • Clean the sensor using MAF cleaner spray; do not touch the sensing element.
  • Reinstall the sensor and reconnect the electrical connector.
• Tools Required: Phillips screwdriver, MAF cleaner spray.

4. Check and Adjust Fuel Pressure

• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail test port.
  • Turn on the ignition without starting the engine to check the pressure; it should match the specified value (usually around 40-50 psi).
  • If the pressure is low, check the fuel pump and filter for issues.
• Tools Required: Fuel pressure gauge.

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  • Remove the fuel rail with injectors attached after relieving fuel pressure.
  • Inspect injectors for clogs; clean them with fuel injector cleaner or use an ultrasonic cleaner if necessary.
  • Reinstall the injectors ensuring O-rings are intact and seated correctly.
• Tools Required: Fuel injector cleaner, ultrasonic cleaner (optional).

6. Replace Engine Coolant Temperature Sensor (if faulty)

• Sub-steps:
  • Locate the coolant temperature sensor near the thermostat housing.
  • Disconnect the connector and remove the sensor using a socket.
  • Install the new sensor, reconnect the electrical connector, and ensure no coolant leaks from the area.
• Tools Required: Socket set.