Oil in airbox & Intake boot 89 325i

[R3vunlimited]

What's up I just recently bought an 89 325i with approximately 170K miles about a month ago and I can't seem to figure out why oil is getting into the airbox and how to prevent it.

When I first got the car I adjusted the valves, changed sparkplugs, changed the oil, new air filter, cleaned the IAC and MAF, and also bled brakes and clutch, but, for some reason, every cold startup blows white smoke and oil is getting to the airfilter somehow. Any help on this would be greatly appreciated, she's gonna be my daily here soon so I need her to pass smog and run well. Also it throws a CEL code 1222 when idling. Thanks!

[R3vunlimited]

I also just replaced the vacuum lines and Intake boot.

[Bullhead]

I also have this, I clean it out every once in a while. From what I have been told (I don't know for sure dangit) these engines do not have an oil evacuation route like a pcv valve or the like. So this is just a normal m20 from what I have been told. I don't know if it's blow by or just non vented crankcase pressure that makes this happen.

[goldenbb]

I'm no authority on the subject, but blow by seems to be the answer. Some oil does go through the vent line in the valve cover and is supposed to get burned up, but if it's a lot, I guess it would seep downhill through the intake and into the airbox? I have read posts where people were having problems with the throttle position sensor due to oil seeping in there and there's even a hack fix where you drill a small hole in the TPS so it can drain.

[xdavesmithx]

is there a lot of oil sludge built up in your crankcase breather hose? that leads to the intake, not the air box, but I had that issue and it seemed to be fairly common

[Cabriolet]

your symptoms pretty much mean, you need need new valve seals. pita job but do remember the engine is 25 years old, all the rubber is failing. but if this doesn't fully fix the issue, you possibly also need new rings as stated before, you are getting blow by.