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

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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative terminal of the battery.
• Ensure the vehicle is on a flat surface and secured with wheel chocks.

2. Inspect and Repair Air Intake System

• Sub-steps:
  1. Remove the engine cover and any obstructing components to access the intake system.
  2. Visually inspect all air intake hoses for cracks or disconnections.
  3. Replace any damaged hoses with OEM parts.
  4. Reassemble the intake system components and reattach the engine cover.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor in the air intake path.
  2. Disconnect the electrical connector and remove the sensor.
  3. Clean the MAF sensor with MAF cleaner or replace it if damaged.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Check Fuel Pressure

• Sub-steps:
  1. Locate the fuel rail and connect a fuel pressure gauge.
  2. Turn the ignition to the ON position without starting the engine to check the pressure.
  3. Compare the reading to manufacturer specifications (usually around 50-60 psi).
  4. If pressure is low, check the fuel pump and fuel filter for issues.

5. Inspect Fuel Injectors

• Sub-steps:
  1. Remove the fuel rail to access the injectors.
  2. Inspect the injectors for clogs or leaks; replace if necessary.
  3. Clean the injectors using a dedicated cleaner or ultrasonic cleaning method.
  4. Reinstall the fuel rail and ensure all connections are secure.

6. Verify Oxygen Sensor Operation

• Sub-steps:
  1. Use a multimeter to check the voltage output of the upstream oxygen sensor.
  2. Replace the oxygen sensor if the readings are outside the normal range (0.1-0.9 volts).
  3. Reconnect all components and ensure proper wiring.