if you are not under warranty, F the dealer, get a set of jack stands or car ramps and some di greaser, clean it up, and then drive it for a day and start to look for the sorce.
could be the valve covers leaking.
i'd rather flush 120 down the bowl then give it to a dealer to "look" for a leak, fvck them.
ramps or a jack and jack stands are always on sale for less than 50 bucks, go buy that instead. and look for yourself.