GTI6 Rattle

[mspdan]

hi guys,

been to look at a gti6 today which has got a rattle..

you will have bare with me as diesel is more my sort of thing but thought someone could pinpoint it for me as i have an idea but wanted bounce ideas off someone else over it..

basically when you start it from cold it has a slight rattle / tap (kind of like piston slap), however after couple mins of it running it stops like its getting oil round..

just wondering if it common fault or something to be worried about...

i presume its simple fix but wanted check even if it is a cheap car

thanks