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

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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the vehicle battery to ensure safety while working on electrical systems.
• Allow the engine to cool down if recently operated.

2. Inspect and Repair Vacuum Leaks

• Sub-steps:
  1. Visual inspection of all vacuum lines and hoses for cracks or disconnections.
  2. Use a smoke machine or carburetor cleaner to detect leaks around the intake manifold and vacuum hoses.
  3. Replace any damaged hoses or gaskets found during inspection.

3. Clean or Replace MAF Sensor

• Sub-steps:
  1. Locate the MAF sensor, typically found in the intake duct.
  2. Disconnect the electrical connector and remove the sensor from its housing.
  3. Clean the MAF sensor with MAF cleaner spray, avoiding any physical contact with the sensor element.
  4. If damaged, replace with a new MAF sensor and reconnect.

4. Check and Adjust Fuel System

• Sub-steps:
  1. Connect a fuel pressure gauge to the fuel rail and turn the ignition on without starting the engine.
  2. Check that the fuel pressure is within the manufacturer’s specifications; adjust or replace the fuel pump if necessary.
  3. Inspect the fuel injectors; clean or replace if clogged or malfunctioning.

5. Test Oxygen Sensors

• Sub-steps:
  1. Locate the oxygen sensors; there should be one before and one after the catalytic converter.
  2. Use a multimeter to check the voltage output of the sensors while the engine is running.
  3. Replace any sensors that do not meet the required specifications.