Every 10,000 km or 6 months — Check spark plugs (Renault Clio 1)

1. The correct operation and performance of the engine depends on the correct functioning of the spark plugs. It is important that the spark plugs installed are suitable for the engine (the appropriate type is defined at the beginning of this Section). If this type is used and the engine is in good condition, the spark plugs should not require attention between scheduled replacements. Cleaning a spark plug is rarely necessary and should not be attempted unless special equipment is available, as the plug can be easily damaged.

2. To remove the spark plugs, first open the hood.

3. On models with F7P engine (with 16 valves), remove the top engine cover, which is secured with two screws (see illustration).



4. Disconnect the high-voltage wires from the spark plugs (see illustrations).







5. To prevent dirt from entering the cylinders, clean the spark plug holes using a clean brush, vacuum cleaner, or compressed air.

6. Unscrew the spark plugs using a special key (see illustration).



7. The condition of the spark plugs can be used to determine the condition of the engine. If the tip of the spark plug insulator is clean and white, without carbon deposits, this indicates a weak mixture or a spark plug that is too hot.

8. If the tip and nose of the insulator are covered with hard black carbon, this indicates that the mixture is too rich. If the spark plug is black and oily, the engine is probably very worn out.



9. If the nose of the insulator is covered with a light brown coating, the mixture is correct and the engine is probably in good condition.

10. If the last spark plug replacement was carried out in accordance with the service schedule 10,000 km ago, they will still be suitable for use for about 10,000 km. However, it is recommended to readjust the gap to compensate for its slow increase during engine operation (approximately 0.025 mm every 1600 km). If the engine condition makes it impossible to repair the spark plug, it should be replaced.

11. The spark plug gap is of great importance. If it is too large or too small, the ignition spark size and performance will be seriously weakened. The clearance shall be as given in the Specifications at the beginning of this Section.

12. To set the gap, measure it with a feeler gauge, then bend the open or closed outer electrode until the correct gap is obtained. The gap is correct if a feeler gauge of the correct size is held firmly and slides freely (see illustration).



13. To check and adjust the spark plug gap, you can use a special tool (see illustrations).







14. Before installing the spark plug, apply a small amount of anti-lock compound to the threads.

15. It is often difficult to insert spark plugs into their holes without distortion. To avoid this, place a piece of hose over the end of the spark plug.

16. Remove the hose (if used) and tighten the spark plug to the tightening torque specified in the Specifications (see illustration).





Install the remaining spark plugs in the same manner.

17. Wipe the high voltage wires, then connect them in the correct order. Where necessary, install the top engine cover.