Leaking antifreeze? An exterior leak would show up with a puddle on the ground. An interior leak would show up in your engine oil with a milky goop on the dipstick or under oil cap, not a good thing. Vacuum leak? A vacuum leak would give you a crappy idle and probably the check engine light would come on with a code for a lean condition.
Rough idle, loss of power, poor mileage.
Intake manifold is leaking, or worse, cracked cylinder most likely tho, the intake manifold.
Intake manifold gasket
Intake manifold at top of engine?
Most likely the intake manifold gasket is leaking.
most time it is caused by intake gasket failure
Intake manifold gaskets are leaking, intake manifold is warped.
leaking gasket try tightening the bolts a little might help
Usually when you leak oil that's an indication that the intake manifold gaskets need to be replaced or your intake manifold is shot.
If it is leaking from a bad head gasket, it is because of a bad head gasket. If it is leaking from a bad intake manifold gasket, it is because of a bad intake manifold gasket.
If really on top then probably the intake manifold gasket ,study it closely .
Most of the time - yes