oil built up inside the intake????

[josev]

i have a 92 190e 2.6 1 year ago the head was rebuilt
all vaccume hose were replace too. the other day i look inside the intake and there is an oil deposit built up which wasn't there when the head was rebuilt and the intake clean out
is there a like a pcv valve inside the valve cover that could off went bad??it is not coming thru the aircleaner housing
it is coming by the by pass hose that goes from the intake to the valve cover.