The walnut shell & dental pick method is effective if not tedious. Are there ANY known catch-can kits for the 5.6 yet? Apparently, Infiniti is well aware of the carbon problem. As much as I want to support virtually every last V8 that is currently made just out of principle, the 3.7's port injection would certainly give me pause to carefully consider...a catch can on that marvelous DI V8 would sure make a difference.