how to fix P0174 code in Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather tools: OBD-II scanner, fuel pressure gauge, socket set, multimeter, cleaning supplies (MAF cleaner).
• Ensure the vehicle is parked on a level surface, and the engine is cool.

2. Inspect Air Intake and Vacuum Lines

• Step 1: Visually inspect all air intake hoses for cracks, leaks, or loose connections.
• Step 2: Carefully remove any damaged or loose hoses and replace them as necessary.
• Step 3: Check vacuum lines for cracks or disconnections and replace any faulty lines.

3. Clean or Replace MAF Sensor

• Step 1: Disconnect the MAF sensor connector and remove the sensor from the air intake duct.
• Step 2: Use MAF cleaner to gently clean the sensor element. Do not touch it with fingers or any tools.
• Step 3: Let the sensor dry completely before reinstalling it. If it's damaged, replace it with a new sensor.

4. Check Fuel Pressure

• Step 1: Connect the fuel pressure gauge to the fuel rail's service port.
• Step 2: Turn the ignition to the "ON" position (do not start the engine) and check the pressure reading.
• Step 3: Compare the reading to the manufacturer's specifications. If low, check the fuel pump and filter for issues.

5. Inspect Oxygen Sensors

• Step 1: Use a multimeter to check the voltage output of the downstream oxygen sensor.
• Step 2: If the readings are outside the normal range, replace the oxygen sensor. Consult the vehicle's repair manual for specifications.

6. Reassemble and Final Inspection

• Step 1: Reconnect all components and hoses that were removed during the inspection.
• Step 2: Clear the error codes using the OBD-II scanner.
• Step 3: Start the engine and monitor for any codes reappearing.