TD5 disco 52 plate Missfire

Just drove about 5 miles nice and steady, doing about 15 mph round corner started to missfire, got to destination about another half mile.
Was there about half hour, got back in motor drove fine for about 3 miles, then missfiring again.
I thought oil maybe in injector loom. but if oil why would it go away for short periods.
Any body got any thoughts on what it may be befour i go in.
thanks.
Mark

Could be worth pulling the plug off and having a look at the end of the loom where it enters the ECU - have a look as this guide for pictures.

Agree with headtester, mine was intermittent, changed it and then fine.

It sounds like typical oil in the injector loom symptoms to me