how to fix P0171 lean code in Tesla Model 3 Highland (2024-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, fuel pressure gauge, multimeter, vacuum gauge, basic hand tools.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect Air Intake System

• Sub-steps:
  1. Visually inspect the air intake hoses and connections for cracks or disconnections.
  2. Use a vacuum gauge to check for leaks in the vacuum system.
  3. If any leaks are found, replace the damaged hoses.

3. Test Fuel Pressure

• Sub-steps:
  1. Connect the fuel pressure gauge to the fuel rail.
  2. Start the engine and observe the fuel pressure readings.
  3. Compare the readings with the manufacturer's specifications (usually around 50-60 psi for Tesla).
  4. If the pressure is low, check the fuel pump and replace if necessary.

4. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor on the air intake duct.
  2. Disconnect the electrical connector and unscrew the sensor from the intake.
  3. Clean the MAF sensor using MAF cleaner and let it dry.
  4. Reinstall the sensor and reconnect the electrical connector.

5. Inspect Fuel Injectors

• Sub-steps:
  1. Remove the fuel injector connectors and inspect for damage.
  2. Perform a resistance test using a multimeter to ensure they are within specification.
  3. If damaged, replace the fuel injectors.

6. Reassemble and Test

• Sub-steps:
  1. Reconnect any hoses and electrical connectors that were removed.
  2. Reconnect the battery terminal.
  3. Start the engine and check for any leaks, ensuring a smooth idle.