Please help with engine noise (video)

[jblaze5779]

Anyone got any ideas on this?
I was wondering if someone could help me figure out what this strange noise coming from my engine is. 2005 z4 3.0i 86k mi m54

Background: For the past couple weeks I would return home from work and would smell faint traces of burnt oil coming from the engine bay of my car. This went on for several days. Finally after a few days I turned the engine off after arriving at my house and got the yellow oil lamp light on my dash. I look up the light and it says "low oil change soon". So I planned on changing the oil the following weekend.

Last weekend rolls around and I parked my car in the driveway to do some handy work in the garage. I then jump in my car to run to the hardware store and upon returning notice a sizeable area of dripped oil on the driveway where my car had been parked. This was enough to alarm me seeing as how I haven't seen any oil drip from the car since I've owned it (just over a year).

I pop the hood and inspect the engine for obvious leaks. The only thing that grabs my attention is the filter housing has a little bit of fresh oil coming from the seal around the housing's screw on cap. From above, I looked into the skid plate and see a puddle of oil pooling up. I find it hard to believe though that this much oil had leaked from the filter housing cap.

I take my other car and grab oil change supplies from autozone. 7qt 5w-30 synthetic and a filter and return home. I changed the oil and notice what couldn't be close to 7qts in the used oil pan. I changed the filter and cleaned up the housing. I then took the car out to the driveway and degreased the engine bay with some simple green and a water hose. I have sprayed down the engine compartment several times before without issue.

I park the car in the garage and hang it up for the night. The next morning I come out to run some errands and upon starting the car, it runs VERY rough. It's stuttering and seems like it's missing a cylinder. After approximately 10-15 seconds the car returns to normal but now I've got this mystery sound that I can't locate or figure out what it could be.

The engine has always been very quite and smooth sounding at idle. Now there is a sort of whiny, almost turbo-ish, sound that varies in intensity with the engine revs. Sometimes it's more obvious than others. It's not a belt noise... to me it almost sounds like a vacuum leak or some kind of sucking noise.

I've inspected the engine bay several times by removing the engine cover and listening closely for the noise. I've had my wife rev the engine and I still can't determine where it's coming from. The noise is just sort of all around the engine not coming from any one specific location. I have noted that the gas mileage has not changed at all and there appears to be no more oil leaking in the engine.

I was wondering if someone might be able to point me in the right direction. I've already inspected the DISA valve and found it to be tight and in seemingly good order. I inspected the coils and tested them individually, they are all good.

The engine used to be relatively quiet with only a nice exhaust note audible. Now it sounds like the xcite bike when your bike was starting to overheat.