Hi. Can you solve my problem, From the very top of the engine on the opposite side of the oil cap there is a rubber hosing that leads to the air filter case, there is a serious vacuum and when i close it there starts a suctioning-whistleing noise from the engine front end. I have the first time in my life when i see this kind of weirdness. And under the exshaust manifold the ventilation collector there is everything as normal, light exshaust gasses. Thanks.

Bad PCV maybe, should be found somewhere around the inlet manifold with a pipe going to the crankcase.