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

Learn how to diagnose and fix P0171 engine too lean issue in Tesla Model S (2012-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Tools Required: OBD-II scanner, vacuum gauge, fuel pressure gauge, MAF cleaner, socket set, torque wrench.
• Disconnect the negative battery terminal to ensure safety while working on the vehicle.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visually inspect all vacuum lines and hoses for cracks or disconnections.
  2. Use a smoke machine to detect any vacuum leaks in the intake manifold or around gaskets.
  3. Replace any damaged hoses or gaskets as needed.

3. Check and Clean MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, typically found between the air filter and throttle body.
  2. Disconnect the electrical connector and remove the sensor from the intake.
  3. Spray MAF cleaner on the sensor element and allow it to dry completely before reinstalling.
  4. Reinstall the MAF sensor and reconnect the electrical connector.

4. Fuel System Inspection

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail and turn the ignition to the "ON" position without starting the engine.
  2. Check the fuel pressure reading; it should be within the manufacturer's specifications (typically 50-60 psi).
  3. If the pressure is low, inspect the fuel pump and filter for issues, replacing them if necessary.

5. Verify Fuel Injector Operation

• Sub-steps:
  1. Access the fuel injectors by removing any necessary components for clearance.
  2. Use a multimeter to check the electrical resistance of each injector; it should match the specifications in the service manual.
  3. Replace any malfunctioning injectors.