i'm trying to diagnose an apparently new oil leak in the engine. it seems especially oily on the side and bottom of the engine under the intake manifold. when i bought the car 3 years ago the flame trap had just been cleaned--and supposedly it was heavily clogged--but now I'm wondering if the oil separator box was never touched. reading the FAQ, I'm suspicious that this may be my problem--either with clogging, or a bad o-ring, or some combination.

my question: can i diagnose if the oil box is clogged simply by trying to blow into the tube that comes out the top? i have checked the flame trap and it is totally clean, as are the small and large hoses going to it. would a clogged oil trap box have any effect on the pressure/vacuum that I can feel at the oil filler cap (AKA the "jiggle test" that I've read about)?

I also just replaced the seal on the filler cap, which was brittle and cracked.