how to fix P0171 code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0171 fuel system issue in Tesla Model S Plaid/Refresh. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts. Ensure the vehicle is parked on a flat surface and the parking brake is engaged.
• Disconnect the negative terminal of the 12V battery for safety.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum hoses and connections for cracks or disconnections.
  2. Use a smoke machine or propane torch to locate vacuum leaks. Apply smoke or propane around suspected areas and watch for changes in engine RPM.
  3. Replace any damaged hoses or gaskets found during the inspection.

3. Check and Clean the MAF Sensor

• Tools Required: MAF cleaner spray
• Sub-steps:
  1. Locate the MAF sensor in the intake duct.
  2. Disconnect the electrical connector from the MAF sensor.
  3. Remove the MAF sensor from the intake duct.
  4. Spray MAF cleaner on the sensor element, avoiding touching it with any tools.
  5. Allow it to dry and reinstall the MAF sensor and connector.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge
• Sub-steps:
  1. Locate the fuel rail and find the fuel pressure test port.
  2. Attach the fuel pressure gauge to the test port.
  3. Turn the ignition key to the "ON" position without starting the engine and check the pressure reading.
  4. If the pressure is below the manufacturer specifications, replace the fuel pump.

5. Inspect and Clean Fuel Injectors

• Sub-steps:
  1. If necessary, remove the fuel rail and injectors from the engine.
  2. Use a fuel injector cleaner kit to clean the injectors or replace them if they are clogged or damaged.
  3. Reinstall the fuel rail and ensure all connections are secure.