how to fix P0171 code on Honda Civic 10th Generation (2016-2021)

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the battery to prevent any electrical issues during repair.
• Tools Required: OBD-II scanner, socket set, multimeter, fuel pressure gauge, inspection mirror, cleaning solvent.

2. Inspect and Repair Vacuum Leaks

1. Visually inspect all vacuum hoses for cracks or disconnections.
2. Use an inspection mirror to check hard-to-reach areas.
3. Replace any damaged hoses with new ones.
4. Reconnect all hoses securely.

3. Clean or Replace MAF Sensor

1. Remove the MAF sensor from the air intake duct.
   • Tools Required: Socket set.
2. Use MAF sensor cleaner to clean the sensor element. Allow it to dry completely.
3. If cleaning does not resolve the issue, replace with a new MAF sensor.

4. Test Fuel Pressure

1. Connect the fuel pressure gauge to the fuel rail test port.
2. Turn the ignition to the ON position (do not start the engine) and check the pressure reading.
   • Compare the reading to the manufacturer specifications (generally between 40-50 psi).
3. If the pressure is low, check the fuel pump and filter, replacing them if necessary.

5. Inspect Fuel Injectors

1. Remove the fuel injectors from the fuel rail.
   • Tools Required: Socket set.
2. Check for blockages or leaks in the injectors.
3. Clean the injectors using an ultrasonic cleaner or replace them if faulty.

6. Reassemble and Reset System

1. Reinstall all components in reverse order.
2. Reconnect the battery.
3. Clear the P0171 code using the OBD-II scanner.