I tried posting over at DB and I am waiting on a response, so i thought i would try here and hopefully get some more answers. 2006 with 47,000 miles. 4in straight exhaust, RCD egr delete, new oil cooler, replaced stc fitting, stock tuned, coolant filter, edge insight. My delta was kinda erratic, so thats when I did the egr delete/oil cooler. Well Its been like 600 miles and i am still getting a lot of white smoke. The week after I put it back together it threw two codes for cylinder contribution on even numbered cylinders, I chocked that up to having air in the lines. After that week it never threw a code again. Average diffrence between temps now is like 5 degrees. I have been monitoring my levels and I dont see a drop in coolant at all. My edge insight shows 47.5 volts at start up and 48 when running. I took it to the dealer and he did a contribution test on it and didnt see any irregularities. He said one injector could be functioning at 60% but if all the others are at 100% it hides the bad one.. Didnt make sense to me but who knows. I am getting an average of like 12.4 mpg which seems kinda low to me. I would swear its my head gaskets but im not losing coolant. Only other thing I notice is while I am accelerating at around 2500 rpms I notice the needle start to flutter and I hear the exhaust waver (almost stutter). The smoke is white with maybe a blue tint, it kinda hangs around for a few seconds, and doesnt dissapear right away. I have no sense of smell, but my friend thought it kinda smelled like fuel but that is not confirmed. So is the tech right ?? am I just loosing an injector or two slowly ??? Over on diesel bombers a guy thinks it is a bad injector o ring.