Smoke on Start-Up

[hardhitter]

I have a 1.8 TQS and noticed that when I start the engine the first 5 seconds or so, it smokes from the tailpipes, as in burning oil. This only seems to happen at the start of it being run that day.
I'm thinking that either the turbo is weeping oil or the engine is letting oil through somewhere. The engine is on 140k and I don't know if the turbo has been replaced. None of the history I have indicates any turbo replacement at least.

Before I investigate further I was wandering if anyone has had the same symptoms and whether the problem is more likely to be turbo or engine related.

 

[Broken Byzan]

Silly question, what colour is the smoke? White, Grey, Black or maybe steam?

 

[aragorn]

If its happening on the first start up that kinda indicates valve stem oil seals, although adding a turbo into the mix can muddy the results.

Warm the engine up, then leave it idling for 5 mins, and then bring it up to 3k and see if it smokes, although again, that wouldnt really help narrow down turbo or oil seals

 

[hardhitter]

It's grey (mixed with water vapour from cat) then turns white (just water vapour) after 5 secs or so.

It can't see it being unburned fuel as the lambda doesn't start working until it's warmed up. I'm sure it doesn't smoke after it's warmed up (although I will double check).