how to troubleshoot P0171 code in Tesla Model S Original (2012-2020)

Learn how to troubleshoot and fix P0171 fuel system issue in Tesla Model S (2012-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts for the repair.
• Disconnect the vehicle's 12V battery to ensure safety during troubleshooting.
• Ensure the area is well-ventilated and free of flammable materials.

2. Inspect and Repair Vacuum Leaks

• Tools Required: Vacuum gauge, basic hand tools.
• Sub-steps:
  1. Using a vacuum gauge, connect it to a vacuum source to check for leaks.
  2. Visually inspect all vacuum hoses and connections for cracks or disconnections.
  3. Replace any damaged hoses or gaskets with OEM parts.
  4. Reconnect the battery.

3. Check and Clean MAF Sensor

• Tools Required: MAF sensor cleaner, screwdriver.
• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Disconnect the MAF sensor electrical connector.
  3. Remove the MAF sensor using the appropriate screwdriver.
  4. Clean the sensor element using MAF sensor cleaner; do not touch the element directly.
  5. Allow it to dry, then reinstall the MAF sensor and reconnect the electrical connector.

4. Test and Repair Fuel Pressure

• Tools Required: Fuel pressure gauge.
• Sub-steps:
  1. Locate the fuel rail and attach the fuel pressure gauge.
  2. Turn the ignition to the "ON" position (do not start) to prime the fuel system.
  3. Check the reading on the gauge against the manufacturer's specifications.
  4. If the pressure is low, inspect the fuel pump and replace it if necessary.

5. Check Fuel Injector Functionality

• Tools Required: Multimeter, fuel injector tester.
• Sub-steps:
  1. Disconnect the fuel injectors' electrical connectors.
  2. Use a multimeter to check the resistance of each injector; it should be within the manufacturer's specified range.
  3. If an injector is faulty, replace it with an OEM part.
  4. Reconnect all electrical connectors.