Intake covered in oil.
Here is my guess if it is towards the front of the motor and the breathers/pcv are dry. Front intake seal is leaking in the corner where it meets the side intake gasket, air is coming from under the car or being blown back from the fan which is causing it to get on the hood. Look down the edge of the timing cover, is there any residual oil there or along the block where the head and block meet? Buy some engine degreaser and clean it up first, shouldnt be that hard to find.