how to diagnose a rough running engine in my Volkswagen Golf MK7 (2015-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Spark Plugs

• Remove the engine cover if applicable.
• Use a spark plug socket to remove the old spark plugs.
• Inspect the old plugs for wear and replace them with new ones.
• Torque the new plugs to the manufacturer’s specifications (usually around 20 Nm).
• Reinstall the engine cover.

3. Clean or Replace Air Filter

• Locate the air filter housing and remove it.
• Inspect the air filter; if dirty, replace it with a new one.
• Ensure the air filter housing is sealed properly before closing it.

4. Test or Replace Fuel Injectors

• Disconnect the fuel lines and electrical connectors from the injectors.
• Use a fuel injector cleaner or replace the injectors if they are clogged.
• Reconnect fuel lines and connectors securely.

5. Replace Ignition Coils (if needed)

• Identify the ignition coil locations and disconnect the electrical connectors.
• Remove the bolts holding the ignition coils in place and carefully extract them.
• Install new ignition coils and torque them to specifications.
• Reconnect the electrical connectors.

6. Inspect Vacuum Lines

• Visually inspect all vacuum lines for cracks or disconnections.
• Replace any damaged lines with new hoses to ensure a proper seal.

7. Perform Compression Test (if needed)

• Remove spark plugs to create access to the cylinders.
• Insert a compression gauge into each cylinder and crank the engine.
• Record the readings and compare them to manufacturer specifications.