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 negative battery terminal to prevent electrical shorts.
• Allow the engine to cool completely before starting work.

2. Inspect and Repair Air Intake System

• Tools Required: Socket set, screwdrivers, vacuum gauge.
• Remove the engine cover (if applicable) to access the air intake.
• Inspect all intake hoses and connections for cracks or breaks. Replace any damaged components.
• Check for vacuum leaks using a vacuum gauge or by spraying soapy water around joints and listening for hissing sounds. Repair or replace any leaking sections.

3. Fuel System Inspection

• Tools Required: Fuel pressure gauge, safety goggles.
• Reconnect the fuel system, ensuring all connections are secure.
• Attach the fuel pressure gauge to the fuel rail and turn the ignition to the "On" position without starting the engine. Check that the fuel pressure meets the manufacturer's specifications (usually around 50-60 psi).
• If pressure is low, check the fuel pump and fuel filter for blockages or failure; replace if necessary.

4. MAF Sensor Cleaning/Replacement

• Tools Required: MAF sensor cleaner, torque wrench.
• Disconnect the MAF sensor electrical connector.
• Remove the MAF sensor from the intake duct by unscrewing the mounting screws.
• Clean the sensor with MAF cleaner to remove dirt and oil buildup. Allow it to dry completely before reinstalling.
• If cleaning does not resolve the issue, replace the MAF sensor with a new one.

5. Inspect and Replace Fuel Injectors

• Tools Required: Socket set, injector puller tool.
• Remove the fuel rail by unscrewing its mounting bolts and carefully lifting it off the injectors.
• Inspect the injectors for clogs or leaks. Test each injector for proper operation using a multimeter or injector tester.
• Replace any faulty injectors, ensuring they are properly seated in the rail when reassembling.