Thanks guys for the help so far in diagnosing my V6 Rangie problem.....
It was indeed an intake air leak.......it was so big though that I couldn't find it so I started again.....
removed plenum and all the gubbins and lo and behold, my new valley gasket has basically tried to flip inside out, which I can only assume is due to crankcase pressure beneath it..........
Strangely, this is exactly the same state the original vallet gasket was in, although that only resulted in oil leaks for some reason......
Anyroad up, as we say oop norf, it is all back together again with a new composite gasket and seals (which was in a unipart bag but not marked front in any way!!) and I refuse to turn the key without asking all you V8 gurus' what is causing this............
And.......where the hell does the crankcase breath from on a 3.5 EFI
All the best for a smooth running 2006 !!
Seeya
Martin