Video tech tip on how to remove a spark plug wire on an engine. This applied to all types of spark plug wires found on vehicles, recreational vehicles, small engines, etc. Although procedures for coil packs which are directly mounted on the spark plug may vary between makes and models. It is very important to take care when removing a spark plug wire as it can be easily damaged, therefore requiring a replacement. Replacements can be expensive, especially if they are only available in a set.
First locate the spark plug wire which you would like to remove. Ensure you are able to gain access to the boot of the spark plug wire. Do not pull the wire portion as you can damage the wire which in turn will require a replacement. Grab firmly onto the spark plug wire boot, then twist in either direction and pull off simultaneously. This ensures the wire will break free is slightly corroded. The rotation also allows for the connection to unclip from the top of the spark plug much easier, putting less strain on the wire. It is normally recommended to apply dielectric grease to the terminal on the top of the spark plug to prevent corrosion and sticking. To reinstall the spark plug wire, just simple push firmly back into place until you either feel or hear a clip.
If you do not twist and pull the wire, grab the wire instead of the boot, or the connection is corroded, the result will be wire failure. The wire itself will either break internally, the wiring insulation may fail, or the connection within the wire can be separated.
Any way that the wire fails, it will need to be replaced. As you can see the terminal on the wire completely separate and the insulation has also broken between the wire and spark plug boot.