how do I fix the P0174 code on my BMW 5 Series G30/G31 (2017-2024)?

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to avoid electrical shorts.

Tools Required:

• OBD-II scanner
• Fuel pressure gauge
• Multimeter
• Socket set
• Torque wrench
• Cleaning solvent (for MAF sensor)

2. Inspect and Repair Air Intake System

• Step 1: Visually inspect all air intake hoses for cracks or loose connections.
• Step 2: Tighten or replace any damaged hoses.
• Step 3: Remove the intake manifold cover and inspect the gasket for leaks.
• Step 4: Replace the intake manifold gasket if any damage is found.

3. Check and Clean MAF Sensor

• Step 1: Locate the MAF sensor, which is typically found in the air intake duct.
• Step 2: Disconnect the electrical connector and carefully remove the MAF sensor.
• Step 3: Use a MAF sensor cleaner to spray the sensor; do not touch the sensor elements.
• Step 4: Reinstall the MAF sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Step 1: Connect the fuel pressure gauge to the fuel rail test port.
• Step 2: Turn the ignition to the "ON" position without starting the engine and check the pressure.
• Step 3: Compare the reading to the manufacturer's specifications; replace the fuel pump if it is below specification.

5. Inspect Fuel Injectors

• Step 1: Remove the fuel rail to access the injectors.
• Step 2: Inspect the injectors for leaks or clogs; use an injector cleaning kit if necessary.
• Step 3: Reinstall the fuel rail and torque the bolts to the manufacturer’s specifications.