Crankcase vaccum issue?

[Jeepfather]

Hey all! This is my first post but i have been poking around on here for a while. A couple months ago i bought a 2001 X5 4.4i with 123k milies. Super clean and everything works. After i got I changed the timing chain tensioner, oil seperator, hoses, and ccv just because i did not know if or when they had ever been done. The last week or so i get a ticking when it gets up to temp. I went to check the oil and could hardly pull the dipstick out. It was like someone was pulling on it from inside. There was also no oil on it. I put it back in and went in the garage. I came back out a few minutes later and pulled it back out very easily and the oil level was fine. It burns no oil and has no leaks, so i have no idea what is going on. Any ideas? Any help would be appreciated. This is my first bmw and i really love everything about it!