my Skoda Octavia NFL (2020-Present) has a rough idle when cold what's wrong

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, multimeter, throttle body cleaner, vacuum gauge.
• Disconnect the battery to avoid electrical shorts.
• Allow the engine to cool before starting work on the intake system.

2. Addressing Error Codes

• Use an OBD-II scanner to retrieve and document any error codes.
• Clear the codes and note if they reappear after a test drive.

3. Inspect and Repair Intake System

• Sub-steps:
  1. Visually inspect all air intake hoses for cracks or leaks; replace any damaged hoses.
  2. Remove the throttle body and clean it thoroughly with throttle body cleaner.
  3. Reinstall the throttle body and ensure all connections are secure.

4. Test and Replace Coolant Temperature Sensor

• Sub-steps:
  1. Disconnect the coolant temperature sensor from the wiring harness.
  2. Use a multimeter to test the resistance of the sensor; compare results with manufacturer specifications.
  3. If out of specification, replace the coolant temperature sensor.

5. Examine and Repair Fuel System

• Sub-steps:
  1. Check fuel pressure using a fuel pressure gauge; ensure it meets manufacturer specifications.
  2. Inspect the fuel filter and replace it if clogged or dirty.
  3. Confirm fuel quality and replace if contaminated.

6. Inspect Ignition System

• Sub-steps:
  1. Remove spark plugs and inspect for wear or fouling; replace if necessary.
  2. Check ignition coils for functionality using a multimeter; replace faulty coils.