how to fix P0171 code on BMW 5 Series G30/G31 (2017-2024)

Solution

1. Preparation

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

2. Inspect and Repair the Air Intake System

• Sub-steps:
  1. Remove the engine cover if applicable.
  2. Visually inspect the intake hoses and connections for any signs of wear or damage.
  3. Tighten any loose clamps and replace any cracked or damaged hoses.
  4. If a leak is found, replace the affected component(s).

3. Clean or Replace the MAF Sensor

• Sub-steps:
  1. Disconnect the MAF sensor electrical connector.
  2. Remove the MAF sensor from the air intake path.
  3. Use MAF cleaner to spray and clean the sensor element carefully. Allow it to dry completely.
  4. If cleaning does not resolve the issue, replace the MAF sensor with a new one.

4. Check and Repair the Fuel System

• Sub-steps:
  1. Inspect fuel injectors for signs of leaks or clogs.
  2. If necessary, clean the fuel injectors using a fuel injector cleaning kit.
  3. Test fuel pressure using a fuel pressure gauge; it should meet manufacturer specifications.
  4. If fuel pressure is low, check the fuel pump and fuel filter. Replace if required.

5. Inspect for Vacuum Leaks

• Sub-steps:
  1. Use a smoke machine or spray carburetor cleaner around vacuum lines and gaskets to detect leaks.
  2. Replace any damaged vacuum hoses or gaskets found during inspection.
  3. Ensure all connections are tight and secure.