2.5td running probs

hi there,im looking for some advice.i have fitted a 2.5td engine out of an 89 defender to my series 3 and having some problembs,hope someone can help...
its been running fine for a year but recently on a long run on the motorway it picked up speed by itself,had more power than normal,had to backed of the throttle to nearly of before it changed speed,then it lost power had to give it full throttle to get it to go atall.it felt like a lincage inside pump was loose and only conecting know and then,if i stoped for half hour it drove normaly for 20miles or so.i replaced the injection pump but still playes up,not as bad,havent been on a long run yetwas told could be running on oil from turbo,looked at that has loads of slop in it but not much oil in pipe work,and if it was oil leaking from turbo backing of throttle wouldent slow engine as it does.
any help would be great,im taking the kids camping soon,dont want to breakdown on the way.
paul.

I have noticed this on my 2.5td too. Just every now and then it will gain power followed by a slight loss of power. I put it down to the veg kit I put in. Maybe it isn't. Either way it would be nice to know what was causing it.

Ta

Is your breather tube from the filler cap connected to the air intake?

No, its a hose that goes nowhere, it dangles down the side of the engine. Is it important?

bye

my breather of filler cap is plumed into air intake infront of the turbo,there is a little oil as expected around it but have worked on many diesels that have loads of oil in pipes and they run ok.
are there any known problembs with the injection pumps?

It's just that if there's excess oil mist coming out of the hose into the air intake hose then the engine can run on the oil mist.