Oil residue on outside of turbo intake duct

[BP5Nut]

Hi all,

So gave the engine bay the once over today when I gave the car a wash, and noticed there was a reasonable amount of oily residue on the outside of the turbo inlet duct, concentrated around two locations; the join between turbo & inlet duct, and where a hose of some sort feeds into the duct. I pulled the intercooler to get a better look, pics below. I also noticed that there is oil on the inside of the intercooler ducting and blowoff valve recirc pipe.

Engine is a EJ20Y (Gen4 Legacy GT 5MT, single twinscroll turbo) with 170000k. Haven\'t really noticed anything out of the ordinary in the way it\'s been running.

I\'m a little concerned that with that amount of residue on the outside of the duct, that there is some sort of leak somewhere - possibly more than one given the two locations.

[loganrasti]

It will be from the engine breathers going into the intake pipe. Will have just become like that over time it\'s nothing major

[lachlan]

give the intercooler a rinse out with degreaser ( petrol) while its off . you have a boundry layer of oil between your charge air and your intercooler

every car since ever looks exactly like yours . the older they are the worse it gets . the factory made it to do it .

a catch can is the solution

[BP5Nut]

Yup gave the intercooler a good clean while it was off, wasn\'t too bad but every little bit helps.

Glad to hear that its normal, that\'s kinda put my mind at rest.

Still a little confused as to how it\'s getting onto the outside of the pipe though. Isn\'t it generally bad if air is getting into/out of the intake system after the AFM?

[lachlan]

yeah it is . but the oil residue seems to do it always . even on brand new vehicles . specially diesels