[MSchfiftyFive]

You guys know what bad plugs look like, right? Heh, if you're replacing them every time they don't look brand new you're doing it wrong and not gaining anything. People run MMT octane booster once, pull their plugs and freak out because they're orange and replace them...that manganese coating has zero impact on spark efficiency, and that's not what denotes a fouled plug. Even the first post, the plugs look fine for another 5-10K miles. It's normal to have slightly higher soot concentration on a DI motor plug on the insulator (white part of the plug) - there's no signs of oil, overheating, knock, or glazing, and a true worn plug would have deteriorated all parts equally (electrodes and insulator) with noticable and uniform cavitation on every exposed piece of the plug - that's not in any of these pics. A true worn plug will also continue to fire just fine at the expense of worse fuel economy from an incomplete burn, and that's after you're pushing them waaaay past due (none of these pics) - just saying, save your money and follow the factory 30K recommendation unless you've fouled them from bad gas or extended driving on a poor tune.