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Here's the procedure how to replace the ignition coil pack of your car.
Understand basic safety procedures. Any time you work on your Ford Focus, you should set the emergency brake and disconnect the negative, or ground, cable from the battery. Some mechanics recommend you isolate the cable to prevent accidental contact, which could spark a connection.
Release the spark plug wires from the Ford Focus ignition coil pack. You may need to pinch or press a release to unlock the wires.
Use a socket set or a small wrench to unbolt the ignition coil connectors. You also need to undo the capacitor electrical connectors. As you work, make note of which connectors go where--this pays off you when you reassemble the parts.
Locate the bracket that holds the ignition coil pack and the electrical capacitor in place. Undo the fasteners that secure them.
Separate the Ford Focus ignition coil pack from the mounting system. Replace the old Focus ignition coil pack with a new one. Verify the new ignition coil pack works with your engine, even if you use a universal ignition coil pack.
Reassemble the parts. If you have a Torque wrench, use it to tighten the ignition coil bolts with 7 inch pounds of torque (10 Nm).
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