how to diagnose P0171 code in Honda Pilot YF3 (2016-2022)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during repair.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamp pliers
• Use a vacuum gauge to test for leaks in the intake system.
• Visually inspect all hoses and connections. Replace any damaged or disconnected hoses.

3. Check Fuel Pressure

• Tools Required: Fuel pressure gauge
• Locate the fuel rail and attach the fuel pressure gauge.
• Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
• If pressure is below specifications, inspect the fuel pump and filter, and replace as necessary.

4. Clean or Replace MAF Sensor

• Tools Required: MAF sensor cleaner, screwdriver
• Locate the MAF sensor in the air intake duct.
• Disconnect the electrical connector and remove the MAF sensor.
• Clean the MAF sensor with MAF sensor cleaner and allow it to dry completely before reinstallation.
• If damaged, replace the MAF sensor with a new one.

5. Inspect and Test Fuel Injectors

• Tools Required: Multimeter, injector cleaner
• Remove the fuel rail to access the fuel injectors.
• Use a multimeter to test the resistance of each injector; compare readings to specifications.
• If injectors are clogged, use an injector cleaner or replace them if necessary.

6. Check Oxygen Sensor

• Tools Required: O2 sensor socket
• Locate the upstream oxygen sensor and disconnect the electrical connector.
• Use an O2 sensor socket to remove the sensor from the exhaust manifold.
• Test the sensor for proper operation using a multimeter and replace if faulty.