how to fix P0174 code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0174 system too lean issue in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle battery to ensure safety during repairs.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdrivers, vacuum gauge
• Instructions:
  1. Remove the engine cover if necessary to access the air intake.
  2. Inspect all hoses and clamps for cracks or looseness; replace any damaged hoses.
  3. Ensure all connections are secure, particularly around the throttle body and intake manifold.
  4. Reinstall the engine cover.

3. Check and Clean MAF Sensor

• Tools Required: MAF cleaner, soft cloth
• Instructions:
  1. Locate the MAF sensor in the air intake system.
  2. Disconnect the electrical connector from the MAF sensor.
  3. Remove the MAF sensor from its housing.
  4. Spray MAF cleaner onto the sensor element and allow it to dry completely.
  5. Reinstall the MAF sensor and reconnect the electrical connector.

4. Test Fuel Pressure

• Tools Required: Fuel pressure gauge
• Instructions:
  1. Locate the fuel rail and attach the fuel pressure gauge.
  2. Turn the ignition to the ON position (without starting the engine) to check for initial pressure.
  3. Start the engine and monitor the fuel pressure against manufacturer specifications; if low, check the fuel pump and filter.

5. Replace Faulty Components

• If any faulty components (like oxygen sensors or fuel injectors) were identified during diagnostics, replace them:
  • Tools Required: Socket set, torque wrench
  • Instructions:
    1. For oxygen sensors: Unplug the electrical connector, unscrew the sensor, and install the new one, ensuring it is torqued to the manufacturer's specification.
    2. For fuel injectors: Remove the fuel rail, replace the injector, and reassemble everything securely.