Might be a stupid question, but any chance this is related to engine temp or time running? It seems that when mine acts up (I have the vagcom ECS off mod, and first thing I always do when I get in any car is shut off all electronic nannies I can) and the only time I can seem to get this to act up is when the engine is not at 100% warmed up. Its so hard to pin point because mine does not interfere every time, sometimes i can roast the tires non stop in first and 2nd, sometimes it kicks on and kills the fun.