Every 45,000 km – removal, inspection and replacement of spark plugs (Fiesta 4)

Ford's maintenance plan requires spark plugs to be replaced every 45,000 km (28,000 miles). But if your Fiesta is reluctant to start or jerks after starting, the spark plugs may be the culprit. Unnoticeable cracks in the insulator during cold engine starting can fill with fuel, which diverts the spark. Under pressure, spark formation may be impaired, even though the plug works fine in the open air. If you don't trust your plugs, replace them with new ones to be on the safe side. Only change the plugs on a cold engine, using a special spark plug wrench or a spark plug socket



SEQUENCE OF WORKS



Fig. 9.6. Removing the high-tension wire tip from the spark plug of the Endura engine

1. Remove the high-voltage wire tips from the spark plugs (Fig. 9.6). The Zetec engine spark plugs are located under the decorative panel on top of the cylinder head cover and are protected from dust and moisture. Be careful when installing - you can damage the spark plug insulator with a regular tool. Therefore, it is recommended to use a special spark plug wrench to replace the spark plugs.



2. Unscrew the spark plugs approximately three turns and thoroughly blow out the spark plug wells with a stream of compressed air to prevent dirt from getting into them and the cylinders during installation.

3. Use a spark plug wrench to unscrew the spark plugs and lay them out on the table in the order they are installed in the cylinders.

4. Before installation, lubricate the threads of the new spark plugs with a thin layer of copper grease and screw them into the holes by hand (without twisting them), then tighten the spark plugs with a spark plug wrench by 1/4 turn (90°), which corresponds to the specified tightening torque of 25 N·m.

5. If you are using used spark plugs, carefully clean the spark plug threads with a brass brush before installing them. Install them in the same way as new spark plugs, but only turn the key at an angle of 15° (the sealing ring on used spark plugs is already compressed).