If it is indeed the vanos or the cylinder head cover gasket, there no reason that you have to bring it to Bmw dealer. Any indy can do this simply for way less. But if you plan on diy may this can help you out http://tis.spaghetticoder.org/s/view.pl?1/07/45/43. Doesn't have 550 but the 545 is pretty similar. GL

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The dependable- 2011 Acura MDX Advanced

The garage decorator- 2008 BMW 550i M Carbon Black

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