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 necessary for the repair.
• Disconnect the negative battery cable to prevent electrical shorts.
• Allow the engine to cool if it has been running.

2. Inspect and Replace Vacuum Hoses

• Step 1: Locate all vacuum hoses connected to the intake manifold.
• Step 2: Visually inspect each hose for cracks, leaks, or disconnections.
• Step 3: Replace any damaged hoses with OEM-spec replacements.
• Tools Required: Pliers, hose cutter, replacement hoses.

3. Clean or Replace MAF Sensor

• Step 1: Disconnect the electrical connector from the MAF sensor.
• Step 2: Remove the MAF sensor from the air intake duct.
• Step 3: Clean the sensor using MAF cleaner spray (do not touch the sensing elements).
• Step 4: If cleaning does not resolve the issue, replace the MAF sensor with a new one.
• Tools Required: Torx or screwdriver set, MAF cleaner.

4. Check Fuel System

• Step 1: Test fuel pressure at the fuel rail using a fuel pressure gauge.
• Step 2: If pressure is low, inspect the fuel pump, fuel filter, and fuel lines for blockages or failure.
• Step 3: Ensure fuel injectors are functioning properly; if necessary, clean or replace them.
• Tools Required: Fuel pressure gauge, injector cleaning kit, socket set.

5. Inspect Throttle Body and Intake Manifold

• Step 1: Remove the throttle body from the intake manifold.
• Step 2: Clean any carbon buildup using throttle body cleaner.
• Step 3: Reinstall the throttle body with new gaskets.
• Tools Required: Throttle body cleaner, gasket scraper, socket set.

6. Reconnect Battery and Clear Codes

• Step 1: Reconnect the negative battery cable.
• Step 2: Use the OBD-II scanner to clear the P0174 code.
• Step 3: Start the engine and allow it to reach operating temperature.