why does my Volkswagen Passat B8 (2015-2022) engine light keep coming on

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Park the vehicle on a level surface and set the parking brake.
• Disconnect the negative battery terminal to ensure safety.

2. Address Fault Codes

• Based on the OBD-II scanner results, identify the specific issue (e.g., P0420 for catalytic converter efficiency).
• If related to the catalytic converter, proceed to the next steps; otherwise, address the specific issue indicated by the codes.

3. Inspect and Replace Components

• For Ignition Issues:

  • Remove the engine cover if applicable.
  • Remove the ignition coils using a socket set.
  • Replace faulty ignition coils and/or spark plugs as necessary, ensuring correct torque specifications (typically 15 Nm for spark plugs).

• For Fuel System Issues:

  • Check fuel pressure with a fuel pressure gauge.
  • Replace the fuel filter if pressure is below specifications or if it’s clogged.

• For Air Intake Issues:

  • Inspect the air filter and replace if dirty.
  • Check the intake manifold for leaks and repair if necessary.

4. Clear Codes and Recheck

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the error codes.
• Perform a test drive to see if the engine light returns.