The ac line that runs along my passenger frame rail was burned through from the 02 bung on my on3 kit.(even through dei heat wrap) So i decided to replace it and while I was taking the turbo back off I noticed some oil build up on the inlet side. This turbo has about 600 miles on it. Oil feed and drain are the ones that on3 supplied. Just want to know if this is normal to have some oil residue or not. Sorry if its a dumb question.