We have a problem with out  Mk3 Golf 1.8 Single point injection, it starts first time but once you pull away after about 50 yards the revs drop right down and then pick up again, this only happens when starting form cold, then it will drive fine all day until the next time you start it from cold. Does anyone have any idea what the problem could be ? 

Could be a number of things including.
Cold start valve,
Water temp sensor,
Lamber sensor,
Ot something like an inlet clean

Thanks for that Danny now all I need to do is find all these things