Us a small propane torch NOT LIGHTED to supply a little fuel to the area with the engine idling. When the propane finds a manifold crack the engine will increase its rpm. Use proper ventillation and be careful.
Intake manifold is leaking, or worse, cracked cylinder most likely tho, the intake manifold.
replace the intake manifold gaskets they have know conditions of leaking
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 really on top then probably the intake manifold gasket ,study it closely .
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.
Most of the time - yes
What's under the intake is not a hose, it's a pipe which a hose attaches to behind the intake manifold near the firewall. If the hose is leaking, it's a relatively easy task to replace it. If the pipe is leaking, you will have to remove the intake manifold which is not an easy task (minimum 6 hours to remove and replace the manifold!)