Lately when driving my 2007 MCS and it's not fully warmed up I sometimes notice LOUD multiple pre-ignition knocks when I step on the throttle say 75%, I'll say about three of them! It's like high intensity lightening in a bottle, when you hear it, it scares the crap out of you! Now I know I should wait until it's fully warmed up to be going anywhere near WOT, but none the less it's something I have noticed and perhaps it could bite me later, a sign of things to come. These high pitched sounds get your attention if you're near the car when it happens. I have had all the timing chain components replaced by my Mini Dealer ($1627), dealer mechanic explained when asked, that he adjusted the timing mechanically on the cams, then checked it when plugged into the computer for programming the timing via the ECU. My only guess with my limited knowledge is carbon build-up on the intake valves, I recently had my valve cover replaced (also PCV since it's integrated) and no longer need to add any oil between 5000 mile oil changes when before I needed a quart every 800 miles. Your help is appreciated! Regards, Systemlord.