how to fix P0174 code in BMW 5 Series F10/F11 (2010-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, hose clamps, screwdrivers.
• Inspect all vacuum hoses and connections for cracks or disconnections.
• Replace any damaged hoses or gaskets found during inspection.
• Use a vacuum gauge to verify that there are no leaks present in the intake system.

3. Clean or Replace the Mass Airflow Sensor

• Tools Required: MAF sensor cleaner, screwdriver.
• Remove the MAF sensor from the intake duct.
• Spray MAF sensor cleaner onto the sensing elements and allow it to dry completely.
• Reinstall the MAF sensor and ensure it is securely connected.

4. Check Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Connect the fuel pressure gauge to the fuel rail test port.
• Turn the ignition to the "ON" position without starting the engine and read the pressure. It should meet manufacturer specifications (generally around 50-60 psi for BMW).
• If the pressure is low, check the fuel pump and fuel filter for issues.

5. Inspect and Clean Fuel Injectors

• Tools Required: Injector cleaner kit, socket set.
• Remove the fuel injectors from the fuel rail.
• Inspect for any clogs or leaks.
• Use an injector cleaning kit to clean the injectors thoroughly before reinstalling.

6. Replace Engine Coolant Temperature Sensor (if faulty)

• Tools Required: Socket set, replacement sensor.
• Locate the coolant temperature sensor on the engine.
• Disconnect the electrical connector and remove the sensor.
• Install the new sensor and reconnect the electrical connector.