Unknown Problem

The /6s always have a little "shimmy" in them. I've heard it described by others as a skip...it just happens to make that sound in the exhaust. Is the engine down on power? Is it exhibiting any issues like fouled plugs, smoking, noises, or vibrations? The first step in my "check out" routine is pull the plugs and inspect them well, and then take a compression reading. Any that seem "out of whack" I do a leak down on. Then go from there. Hard to tell much accurately from keeping your hand over a pipe...