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.

2. Inspect and Repair Vacuum Leaks

1. Visually inspect all vacuum hoses connected to the intake manifold.
2. Use a smoke machine or carburetor cleaner to detect leaks; spray around suspected areas and observe for changes in engine RPM.
3. Replace any damaged or cracked hoses and re-check for leaks.

3. Clean or Replace MAF Sensor

1. Locate the MAF sensor in the air intake duct.
2. Disconnect the electrical connector and unscrew the MAF sensor from the duct.
3. Clean the MAF sensor using MAF cleaner spray (do not touch the sensor elements).
4. If cleaning does not resolve the issue, replace the MAF sensor with a new one.

4. Check and Adjust Fuel Pressure

1. Locate the fuel pressure test port on the fuel rail.
2. Attach the fuel pressure gauge and start the engine.
3. Compare the fuel pressure reading to the manufacturer's specifications (usually between 40-50 psi for most Hondas).
4. If pressure is too low, check the fuel pump and filter; replace them if necessary.

5. Inspect and Clean Fuel Injectors

1. Remove the fuel rail with the injectors attached (follow service manual for specific steps).
2. Clean the injectors using a dedicated injector cleaning kit or replace them if they are clogged or damaged.

6. Reassemble and Reset

1. Reinstall the intake duct and any components removed during the inspection.
2. Reconnect the negative battery terminal.
3. Start the engine and allow it to idle for a few minutes.