ah haaa.......so checked for oil (nope - no obvious wet patches), next checked breather hose (or think I did, could have been looking at the wrong thing!).....anyway whatever I was looking at seemed fine as well. So started engine from cold and yes can hear a 'ticking' that does not appear to be quite right.......to be certain went for a blast again and hey presto, can't breathe again (but feel strangely relaxed and all is good with the world).......get home pop bonnet and the ticking is not really as obvious now car has warmed up and doing a very convincing impression of my BBQ after several beers and a 'forgotten' pack of sausages.

I'll get the garage to check EVERYTHING but am pretty ceratin its the manifold as the smell is like sticking you face near the exhausts and taking a nice big deep breath.........not entirely happy but feel better now it seems clear the manifold is the most likly problem.

Appreciate the help very much from you both in helping me narrow down the potential causes ................right off to empty the kids piggy banks while they sleep to pay for this