my Volkswagen Passat B8 (2015-2022) is stalling at stop lights, what could be wrong?

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, fuel pressure gauge, multimeter, cleaning supplies (throttle body cleaner).
• Disconnect the battery to ensure safety while working on electrical systems.
• Allow the engine to cool before proceeding with any inspections.

2. Clean the Throttle Body

• Remove the air intake duct to access the throttle body.
• Use throttle body cleaner and a soft brush or cloth to clean the throttle body. Ensure the butterfly valve operates smoothly.
• Reattach the air intake duct securely.

3. Inspect and Replace the Idle Air Control Valve

• Locate the idle air control valve (typically near the throttle body).
• Disconnect the electrical connector and remove the mounting screws.
• Inspect the valve for carbon buildup; clean if necessary or replace if damaged.
• Reinstall the valve and reconnect the electrical connector.

4. Test and Replace Fuel System Components (if necessary)

• Connect a fuel pressure gauge to the fuel rail.
• Check the pressure against manufacturer specifications (usually around 50-60 psi).
• If pressure is low, inspect the fuel pump and filter for blockages or damage.
• Replace the fuel pump or filter as needed.

5. Inspect Ignition Components

• Remove spark plug wires and inspect the spark plugs for wear; replace if necessary.
• Check ignition coils for proper function using a multimeter. Replace any faulty coils.