Originally Posted by
chaffe
Sounds like an air leak in the fuel system mate.
2nd that. Check pipes to and from your filter housing and pump
A bit of grey smoke is common on startup tbh.
Mine is a tdi with 115'000 on it and itll start after a couple cranks and run lumpy for a minute or 2 and smokes grey until warm. I always, when possible, run it for about 5 before taking it out.