Yep. They're little heat shields to keep the wires from suffering accelerated disintegration.

Getting the plug wires off is a pain in the butt. Use a pair of leather gloves. They're just about the best thing available for underhood work of that variety, as long as you don't soak them with oil. You can get the plug wires off, and get the plugs out without gashing yourself silly from the little heat shields.

Also, sometimes a 12" extension on the ratchet helps a lot when yanking the plugs out. I usually use a swivel head long-handle ratchet, plus an extension. Totally out of harm's way, except for the last plug, on which you might need to shorten the extension or remove it altogether.

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Chris Herbst, near Chicago, IL. 93 940, 91 240, 90 240, 88 740, 87 240