my Volkswagen Golf MK7.5 (2020-Present) has a rough idle when cold what's causing it

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical short circuits.
• Allow the engine to cool down before starting work.

2. Replace Spark Plugs

1. Remove the engine cover (if applicable) using a socket set.
2. Disconnect the electrical connectors from the ignition coils.
3. Remove the ignition coils using a socket or wrench.
4. Use a spark plug socket to carefully remove old spark plugs.
5. Inspect the condition of spark plugs and replace them with new ones, ensuring proper gap.
6. Reinstall ignition coils and reconnect electrical connectors.
7. Reattach the engine cover.

3. Clean or Replace Air Filter

1. Open the air filter housing by unfastening screws or clips.
2. Remove the old air filter and clean the housing with a damp cloth.
3. Install a new air filter, ensuring it fits snugly in the housing.
4. Secure the housing cover back in place.

4. Fuel System Inspection

1. Connect a fuel pressure gauge to the fuel rail.
2. Turn the ignition on (but do not start the engine) to check fuel pressure.
3. Compare the reading with manufacturer specifications; replace the fuel pump if pressure is low.
4. If the pressure is within range, consider cleaning fuel injectors using a fuel system cleaner.