Increasing oil levels - what's the fault?

The oil level in my 2009 Ford Focus 1.6 diesel is increasing and I have to change the oil every two weeks to save the engine. The coolant level doesn't change and the oil isn't murky when I change it, so I'm sure it's not water. I've had the injectors reconditioned and the injector seals replaced. The mechanic did a compression test and said the engine was at approx 80%. The fuel economy has dropped from 55 to 43mpg, and the power has dropped off also. I've had the dpf replaced 4 months ago and this problem only really started after the dpf was replaced, and I read somewhere else that the engine could be trying to constantly regenerate the dpf, although I don't understand how this would result in diesel entering the oil sump. Does the engine oil lubricate the fuel pump? Could there be a leaking seal on that allowing diesel into the oil that way?
Your thinking is correct. The problem is overfuelling to actively regenerate the Diesel Particulate Filter, but your engine is overfuelling too much and the excess fuel is sinking into the sump, contaminating the lube oil and raising its level. If it gets to high the engine will run on its sump poi and be unstoppable until it blows up. The ECU needs reprogramming to prevent this.
Answered by Honest John on

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