After about 3-4k miles my oil warning light has come on as it needs a top up.

Any thoughts on what it could be causing so much loss? I've had a read around seen numerous suggestions(car has only done 91k miles)

I recall before my last service I had to top up every 2 weeks or so.

I used to pop in 100-200ml and so it seems that it seems fairly consistent with consumption at the moment.

I know the engines normally do consume a little oil, but I guess this is "within parameters" and I just have to live with topping it up?

With age and mileage, check the breather pipe going to the inlet is clear and not full of crud.

 

You may find the oil could be seeping through the turbo oil seals and gradually being consumed by the engine.

 

Worse case scenario is that the piston rings could be worn and oil running pass them or the valve stem seals have passed it and the oil is leaking through that way, but the smoke would be obvious with blue smoke on start up when cold etc...

Cheers, I've got another 5k oil change coming up soonish, I'll get it sorted out then