i have a 2004 wrx and recently noticed oil burning (smoking) off the bottom of the up pipe where it meets the exhaust manifold. about 2 months ago i had the valve cover gasket and cam seals and oil pump seal replaced. however i am still getting oil burning off my up pipe. this only leaves me with the turbo return line. i checked it today and noticed it was leaking a bit however can that oil manage to make its way onto the up pipe???