With no details to go on like how much oil, it's most likely condensed fumes from a non-working PVC system.
May 2, 2014 at 8:02 PM
WRENCHTECH
CAR REPAIR CONTRIBUTOR
20,761 POSTS
That is usually caused by excessive compression blowby past the rings due to wear. Make sure the PCV system is working properly first.
May 3, 2014 at 2:51 AM
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