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

Learn how to troubleshoot and fix P0171 engine lean condition in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool down if it has been running.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  • Visually inspect all vacuum hoses connected to the intake manifold for cracks or disconnections.
  • Use a smoke machine or carburetor cleaner to identify any leaks; apply the cleaner around suspected areas and watch for changes in engine idle.
  • Replace any damaged hoses or gaskets found during the inspection.

3. Clean or Replace MAF Sensor

• Sub-steps:
  • Locate the MAF sensor in the intake system.
  • Disconnect the electrical connector and remove the sensor from the intake tube.
  • Clean the sensor with MAF sensor cleaner and allow it to dry completely before reinstallation. If damaged, replace it with a new MAF sensor.

4. Check and Adjust Fuel Pressure

• Sub-steps:
  • Connect the fuel pressure gauge to the fuel rail test port.
  • Turn the ignition to the "on" position (do not start the engine) to check the fuel pressure reading.
  • If pressure is below specifications, inspect the fuel pump and filter for issues. Replace as necessary.

5. Inspect Fuel Injectors

• Sub-steps:
  • Remove the engine cover if necessary to access the fuel injectors.
  • Visually inspect for any leaks or fuel residue around the injectors.
  • Perform a resistance test on the injectors with a multimeter to ensure they are within specifications. Replace faulty injectors.

Tools Required:

• OBD-II scanner
• Vacuum gauge
• Smoke machine or carburetor cleaner
• Fuel pressure gauge
• Multimeter
• Socket set

Parts Required:

• Vacuum hoses (as needed)
• MAF sensor (if found faulty)
• Fuel filter (if necessary)
• Fuel injectors (if found faulty)

Estimated Repair Time: 2-4 hours

Safety Warnings:

• Disconnect the battery before working on electrical components.
• Allow the engine to cool before performing any repairs to prevent burns.