I'm still wondering where this oil is coming from,is it blow-by coming up(?) the intake manifold? The inside (clean)of the air cleaner is spotless,no oil grime at all.The outside was caked with grime,black as diesel oil.I could still see the red K&N filter oil on the upper 2/3 of the air cleaner.My car doesn't use more than 1/2 a litre between oil changes so I'm