Hey guys. Frustrated 1M owner here. about 10 months ago I had this weird problem where my 1M would randomly rev on its own. The car would rev between about 1000 and 400 RPMs. It wouldn't do this constantly, but it would show up about every couple minutes. I ended up taking it the BMW dealer who diagnosed it with a "stress crack in the upper cylinder head cover/crankcase vent valve malfunction" Car seemed fine after that as I drove it a few hundred miles. The car has now been sitting for about 6 months (I did fill the tank and put Stabil in it right before I put it way). Today I turned it on, waited a minute, back out of the garage and the same problem. Random revving. At this point - WTF! Is there a way I can inspect the vent valve myself?
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