how to fix rough running and misfires on Renault Clio V (2019-Present)

Learn how to diagnose and fix rough running and misfires on Renault Clio V. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool before beginning work.

2. Replace Spark Plugs and Ignition Coils

• Tools Required: Socket set, torque wrench, spark plug socket.
• Remove the engine cover if applicable.
• Use the spark plug socket to carefully remove each spark plug. Inspect for signs of wear or fouling.
• Replace old spark plugs with new ones, ensuring to properly gap them according to the manufacturer specifications (typically around 0.8-1.1 mm).
• Remove the ignition coils by disconnecting the electrical connectors and unscrewing them.
• Install new ignition coils and torque them to the manufacturer’s specifications (usually around 10-12 Nm).

3. Clean or Replace Fuel Injectors

• Tools Required: Fuel pressure gauge, injector cleaning kit.
• Disconnect the fuel pump relay and crank the engine to relieve fuel pressure, then disconnect the battery.
• Remove the fuel rail to access the injectors, taking care to note the orientation of each injector.
• If cleaning, connect the injectors to the cleaning kit and run the cleaning solution through them as per the kit instructions.
• If replacing, install new injectors and ensure they are seated correctly in the rail.
• Reassemble the fuel rail and reconnect everything.

4. Inspect and Clean the Air Intake System

• Tools Required: Screwdrivers, cleaning spray for MAF sensor.
• Remove the air intake duct to access the MAF sensor.
• Clean the MAF sensor using a dedicated MAF cleaner spray, avoiding contact with the sensor elements.
• Check the air filter and replace it if dirty or clogged.
• Reassemble the air intake duct securely.

5. Check for Vacuum Leaks

• Tools Required: Vacuum gauge, smoke machine (if available).
• Inspect all vacuum hoses for cracks or disconnections.
• Use a vacuum gauge to check for proper vacuum levels. A reading below normal indicates possible leaks.
• Repair or replace any damaged hoses.