how to diagnose a P0171 code on my Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose 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 necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical issues.

2. Inspect and Replace Vacuum Lines

• Sub-steps:
  1. Visually inspect all vacuum lines connected to the intake manifold for wear or damage.
  2. Replace any damaged vacuum lines with OEM parts.
  3. Reconnect all lines securely.

3. Clean or Replace MAF Sensor

• Tools Required: MAF cleaner, Torx screwdriver
• Sub-steps:
  1. Locate the MAF sensor in the air intake duct.
  2. Remove the MAF sensor by unscrewing it with the Torx screwdriver.
  3. Clean the sensor with MAF cleaner or replace it if necessary.
  4. Reinstall the MAF sensor and ensure it's properly secured.

4. Inspect Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail.
  2. Turn the ignition to the "on" position without starting the engine to check fuel pressure.
  3. Compare the reading to the manufacturer's specifications; replace the fuel pump if pressure is low.
  4. Inspect fuel injectors for leaks or blockages and replace if necessary.

5. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0171 code.
  3. Start the engine and check for any reoccurrence of the code.