Car has felt a bit down on power and the mpg hasn't been good, I put it down to trying v power, but I think I was wrong, is this the cause? What's the problem and fix?

Is it leaking oil or somthing?

Or am I missing the point? Haha

No there is a build up of what looks like exhaust soot on the oil drain and the turbo looks like it's coming from the join of the exhaust housing