Air Pulsating out oil cap hole & Smoke occasionally out Exhaust?!?!
 

Sometimes there will be smoke that smells kind of like oil burning off thats dark greyish in color that doesnt dissappear when it hits the air, it kind of stays in a smoke form and floats off with the wind out the exhaust.

I figured its my turbo cause it happens only at idle. I never get smoke when I drive. And it takes a couple of minutes at idle for this to happen when it sits idling, and sometimes it just wont happen at all. It comes and goes.

I had 2 previous SR's in a 240 I sold recently, and the last one did the same exact thing with the smoke out the exhaust but I never checked the Oil cap for air comming out, but someone told me its most likely the turbo, when it smokes at idle. So I figured thats what this is.....till:

I opened my oil cap when it was idling tonight after a hard run, and there was Pulsating air comming out the valve cover!!! What does this mean?

I have searched, and I found nothing that settles my stomach with this mystery

can someone tell me if this is normal please?

^ that sounds normal to me.