why does my Volkswagen Golf MK7 (2015-2019) check engine light keep coming on

Solution

1. Preparation

• Gather tools and parts for the repair.
• Disconnect the battery to ensure safety while working on electrical components.
• Tools Required: OBD-II scanner, socket set, multimeter, torque wrench, vacuum gauge.

2. Repairing Ignition System

• 1.1. Remove Engine Cover

  • Use a socket set to remove the bolts securing the engine cover.

• 1.2. Replace Spark Plugs

  • Remove old spark plugs using a spark plug socket.
  • Install new spark plugs, ensuring they are gapped correctly (refer to manual for specifications).
  • Torque to manufacturer specifications (usually around 18 ft-lbs).

• 1.3. Inspect and Replace Ignition Coils (if necessary)

  • Disconnect the electrical connector from each ignition coil.
  • Remove the coils using a socket set.
  • Install new coils, ensuring they click into place, and reconnect the connectors.

3. Vacuum Leak Repair

• 2.1. Inspect Hoses and Gaskets
  • Visually check hoses and gaskets for cracks or disconnections.
• 2.2. Replace Damaged Components
  • Replace any damaged hoses with new ones, ensuring secure connections.
  • Use a vacuum gauge to test for leaks after repairs.

4. Exhaust System Inspection

• 3.1. Check for Leaks
  • Inspect exhaust manifold, pipes, and catalytic converter visually.
  • Use a sound check or smoke test to identify leaks.
• 3.2. Replace Damaged Parts
  • Replace any damaged components with OEM or high-quality aftermarket parts.

5. MAF Sensor Cleaning/Replacement

• 4.1. Remove MAF Sensor
  • Disconnect the electrical connector and unscrew mounting bolts.
• 4.2. Clean Sensor
  • Use MAF cleaner spray to clean the sensor element.
• 4.3. Reinstall Sensor
  • Reinstall the sensor and reconnect the electrical connector.