how to fix P0171 code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0171 fuel system issue in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts. Ensure the vehicle is parked on a flat surface and the ignition is off.
• Tools Required: OBD-II scanner, socket set, multimeter, fuel pressure gauge, cleaning tools for MAF sensor.
• Safety Warnings: Disconnect the battery before working on electrical systems. Allow the engine to cool before starting repairs.

2. Inspect and Repair Air Intake System

• Step 1: Visually inspect the intake hoses for cracks or disconnections.
• Step 2: If any leaks are found, replace the damaged hoses with new ones.
• Step 3: Reconnect any disconnected hoses securely.

3. Check and Clean the MAF Sensor

• Step 1: Locate the MAF sensor in the air intake duct.
• Step 2: Disconnect the electrical connector and remove the MAF sensor.
• Step 3: Use MAF sensor cleaner to gently clean the sensor wires. Allow it to dry completely before reinstalling.
• Step 4: Reinstall the MAF sensor and reconnect the electrical connector.

4. Test Fuel System Components

• Step 1: Connect the fuel pressure gauge to the fuel rail.
• Step 2: Turn the ignition to the ON position (without starting) and check the fuel pressure. It should meet the manufacturer's specifications.
• Step 3: If the pressure is low, check the fuel pump and replace it if necessary.
• Step 4: Inspect the fuel filter and replace it if it is clogged.

5. Inspect Fuel Injectors

• Step 1: Remove the fuel injector connectors.
• Step 2: Use a multimeter to test the resistance of each injector. Replace any that are out of specification.
• Step 3: If needed, use a fuel injector cleaner to unclog any blocked injectors.