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. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a level surface, and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Repair Air Intake System

• Sub-steps:

  1. Visually inspect all air intake hoses and connections for cracks or loose fittings.
  2. Tighten any loose clamps or replace damaged hoses as needed.
  3. If leaks are found, replace the defective components.

• Tools Required:

  • Screwdriver set
  • Hose clamps

3. Clean or Replace MAF Sensor

• Sub-steps:

  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the electrical connector and remove the sensor.
  3. Clean the sensor with MAF cleaner spray, ensuring no residue remains.
  4. If the sensor is damaged or cleaning does not resolve issues, replace it with a new one.

• Tools Required:

  • Torx screwdriver
  • MAF cleaner spray

4. Check Fuel Pressure

• Sub-steps:

  1. Connect a fuel pressure gauge to the fuel rail test port.
  2. Turn the ignition to the ON position (without starting the engine) and check the fuel pressure reading.
  3. Compare the reading to manufacturer specifications and replace the fuel pump if pressure is below spec.

• Tools Required:

  • Fuel pressure gauge

5. Inspect Fuel Injectors

• Sub-steps:

  1. Remove the engine cover if necessary to access the fuel injectors.
  2. Check for any signs of fuel leakage around the injectors.
  3. Use a multimeter to test the resistance of each injector; replace any that are out of spec.

• Tools Required:

  • Multimeter
  • Injector removal tool (if applicable)