I had the same problem and it was the oil cooler o ring. You will have to take off the oil filter and there is a nut you will have to unscrew. The o ring is about $50 at the dealer, but I notice that my oil filter o ring was the same size so I used it off of one of my old filters, and I hav'nt had any problems since and its been about 8 months now.

 

Thanks for the input, I'll probably do both the O-Ring and valve cover gasket.

 

Yea just make sure it is your valve cover because I don't think it's a cheap job and it will be a waste to change the V gasket if nothing is wrong with it

 

same dip

 

Sounds like oil is pooling when the car sits and its burning on the manifold shields or something else...I'm gonna say V.Cover gaskets also