my Skoda Octavia NFL (2020-Present) has a rough idle in cold weather, what's the cause?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent any electrical shorts.
• Allow the engine to cool down prior to working.

2. Inspect and Replace Spark Plugs (if needed)

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the engine cover if applicable.
• Disconnect ignition coil connectors and remove the coils from the spark plugs.
• Use the spark plug socket to remove the spark plugs.
• Inspect the spark plug condition. If worn or fouled, replace them with OEM-spec plugs.
• Torque the new spark plugs to the manufacturer’s specifications (usually around 22 lb-ft).
• Reinstall ignition coils and reconnect connectors.

3. Check and Replace Idle Air Control Valve (if faulty)

• Tools Required: Screwdriver set, socket set.
• Locate the IAC valve (typically on the throttle body).
• Disconnect the electrical connector and remove the mounting screws.
• Inspect the IAC valve for carbon buildup and proper functionality.
• If malfunctioning, replace with a new IAC valve.
• Reinstall the IAC valve and reconnect the electrical connector.

4. Inspect and Repair Air Intake System

• Tools Required: Screwdriver set, vacuum gauge.
• Inspect the air filter for clogs and replace if necessary.
• Check the intake hoses for cracks or loose connections.
• Use a vacuum gauge to test for any vacuum leaks in the system.
• Repair or replace any damaged hoses.

5. Verify Engine Coolant Temperature Sensor

• Tools Required: Multimeter.
• Locate the engine coolant temperature sensor.
• Disconnect the sensor and test its resistance using a multimeter.
• Compare the readings with the manufacturer's specifications.
• Replace the sensor if it is out of specification.