how to fix P0171 code in my BMW X5 G05 (2019-2024)?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative battery terminal to avoid electrical shorts.
• Allow the engine to cool down before starting work.

2. Inspect and Repair Air Intake

• Tools Required: Screwdriver set, hose clamps, vacuum gauge
• Check all air intake hoses and connections for leaks:
  • Remove the engine cover if necessary.
  • Inspect hoses for cracks or disconnections.
  • If leaks are found, replace damaged hoses or re-secure loose connections.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner, soft cloth
• Remove the MAF sensor from the air intake:
  • Disconnect the electrical connector from the MAF sensor.
  • Unscrew the MAF sensor and carefully remove it.
  • Clean the sensor with MAF cleaner and a soft cloth. If damaged, replace it with a new one.

4. Check and Adjust Fuel Pressure

• Tools Required: Fuel pressure gauge, wrench set
• Connect the fuel pressure gauge to the fuel rail:
  • Start the engine and observe fuel pressure readings.
  • If the pressure is low, check the fuel pump and fuel filter for blockages or failures.
  • Replace the fuel pump or filter if necessary.

5. Inspect Fuel Injectors

• Tools Required: Injector cleaning kit (optional), multimeter
• Remove the fuel injectors from the engine:
  • Disconnect the electrical connectors and fuel lines.
  • Inspect for clogs or leaks. Clean injectors using a cleaning kit or replace them if faulty.

6. Verify Engine Coolant Temperature Sensor

• Tools Required: Multimeter
• Locate the engine coolant temperature sensor and test it:
  • Disconnect the wiring harness and measure resistance with a multimeter. Compare readings with manufacturer specifications.
  • Replace the sensor if readings are out of range.