Hi All,

Bought an '03 MCS 57K a couple months ago and when I changed the air filter, the bottom was covered w/oil. I checked/topped oil and in 2K miles I'm down 1/2qt oil w/no visible signs of seepage/leakage. OK, I haven't checked my 'new' air filter, but I'm pretty sure of the outcome when I do. Are we talking a valve/seal issue? Car runs and performs great, throwing no codes, but I want to put a CAI and 15% SC pulley, etc on it and want to know what I'm up against. Any insight is greatly appreciated.

Thanks!

 

I can't tell by the post, but many aftermarket reusable filters require oiling before use (with special oil) Often, after they get hot, oil can pool under the filter. At a cooler temp, it is stuck in the filter, but when heated, it drips.

Just a thought.

 

I wish it were that simple. It has a stock intake as of now. No smoke from the exhaust. I did buy/hang a cat-back system, but this was an issue prior to and I can't imagine anything to do with that.

 

Clean your IC. Must be very oily by now.

 

bad vlaves/seats need head recon do leak check test

 

msmax96, my worst fear. Any clue how much $$$? I got the car for 9K US, so I have room for recon/mods. ;-(

 

If its not burning a lot of oil and it is just pooling you may have a PCV stuck open... very rare though. If you remove the intercooler and its full of Oil sometimes the supercharger gear oil leaks past the seals and it looks a lot like fresh engine oil. I have never seen it where any of the oil would build up in the airbox

 

There is no way for oil to get to that location from the engine. It has to have come from the air inlet at the front of the engine or from the filter.

Are you using the stock paper filter? Was this the first time you have replaced the filter? Could it have had a K&N filter before?

 

Thanks Calz and MINI33342 for the replies. Clearly I have to let a mechanic look at it. The filter appeared stock to me, I have only had the car for 3K miles and it runs/performs great but I've never driven another MC. I'm taking that car to my mechanic at a body shop who is quite good, he rebuilt my cooling sys on my 540, but don't know his ability to diagnose MC issues. Changing all fluids Monday and will monitor the oil and check the air filter I replaced a month ago when I found it VERY oily. I do not know if it was SC oil or motor oil, but confident it was not an aftermarket filter requiring oil that had been overly oiled. No warning lights on, but I have not hooked it up to an OBDII reader w/BMW codes. I appreciate all of your thoughts and advice and hope I don't need a new head or I'll be 'tricking it out' for more $ than I had planned. thanks

 

Just so you know, they do make aftermarket filters for the stock airbox. The do look stock.

http://www.bavauto.com/fland.asp?par...urce=33%202239

 

I am having the same problem. New to me 06 MCS has black oil on the air filter. I did purchase an oil catch can.....hopefully this will catch the oil from blowing back. It seems it would be a known issue if there are so many aftermarket catch cans available.