bollox mate,its on its way out no engine is designed to rattle at ANY point in there life,,, nobody who sells a car with a rattle will say " its fine at the moment but its gonna start getting worse then die"

people buying cars will belive the " it should rattle on start up then shut up after a few seconds" cause the noise goes,,,,,,,, just like when you melt a engine or it starts to smoke/knock its pants off you turn the engine off and start it again in the mornin just incase its fixed the issue,,, and if it done happen you put it down as a " close call"

vanos is fucked with a rattle,,,, thats what the rattle is telling you just its not totally fucked, its the vano's way of saying " get me looked at before i die and really fuck your pocket "