I have oil leakage showing up on the hose for the “charge air induction tract” (#18 on diagram below)...where the hose connects to the "cool side" (I think) of the intercooler. Oil seapage appears at the (2) locations shown by the arrows. I thought that hose carries air…no oil should be in there? Any ideas?

 

The crankcase vent system vapors, which are oil vapors, condense at low points. You can remove hose, clean the neck and inside of hose and re-install and see if it seals well enough to stop the seepage.

 

So does it operate like this? hot air comes from the turbos IN to the opposite side of the radiator thing (intercooler?)...that air gets cooled. In the process of cooling, the very small particles of oil in the air condense. The cooled air and tiny bits of oil then come out the side of the radiator (intercooler?) where I am seeing the leak. The cooled air (and oil I guess), move up the "exit" hose and get routed to the exhaust. Do I have that right? Is so...where is that condensed oil SUPPOSE to go...??

From memory, I think the clamp for the hose on to the intercooler is a spring type clamp...not a normal hose screw clamp...so there really won't be a way to tighten it

 

The pressurized cooled air coming out of the intercooler (that has some oil vapor in it) is routed through the charged pipe into the intake manifold (not to the exhaust) via the throttle housing. Some people install an oil catch can to trap this oil vapor which would otherwise be sent to the intake manifold to be burned off in the combustion chambers, but often ends up as carbon, coating the inside of the manifold and the back of the intake valves causing the notorious intake manifold carbon buildup problem.

 

I would first wipe it down and check around the oil filter housing for leaks since it is in that area. Then after a week or two check back again to see where the leak is coming from. You will always have a little bit of blow by that comes from the turbos oil system. The oil that handyben is talking about deals with the oil vapor that comes from the PCV that vents to the rear air filter intake pipe. The occ will help with eliminating that oil from recirculating in the intake however will do nothing for the blow by.

 

No it has to be getting on there from somewhere else. The unit is used to cool the air from the turbos prior to entering the engine for combustion. It's called a CAC or Charge Air Cooler. Inter cooler use liquid not air.

Have a look at the two oil lines that connect to the lower side of the oil housing fill unit. The cost 0.10 cent and are easy to replace and if leaking could allow oil to run down. Thats just another source to add to the other recommendations that others have already provided.

 

I'm not sure what you mean "oil housing fill unit"...? If you mean the oil filter housing...that is clean and dry. The oil really appears to be leaking from inside that 3" hose...where the hose clamps to the intercooling.

 

I have checked this area..it is clean and dry.
I think this is my issue. I think the oil vapors exiting the intercooler are condensing and causing an accumulation of oil at the junction where the hose meets the exit of the intercooler...and it's leaking out of that connection. So is this something I'm just gonna have to live with?

 

I can't imagine why you would have oil inside your charge air cooler hoses other than maybe some slight residual film if some kind. It has to be coming from somewhere else and seeping in from a connection or something. Ok, my recent post I meant what you thought, the oil filter housing. This stupid ass iPad! Anyway, oil typically falls, so this why I suggested to check the two lines. They are kinda hidden a bit. Also a friend of mine had a cracked cap that drove him crazy. It only leaked when car was hot and the material must have been expanding or something.

Again, you don,t have a intercooler, those have liquid inside for cooling. Your car has a CAC and uses air so no oil should be inside...








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