Cooper S clattery on start up

[funboxster]

My wife and I have noticed in the last couple of weeks that her 21 plate petrol S convertible is noisy when started from cold and you're outside the car. Sounds like a diesel! It seems to settle down once warm. Cooler weather perhaps?

Her two previous S's (15 & 18 plates) weren't this noisy, but they've changed the dynamics on the engine, ie bhp/torque.

Anybody else noticed this on theirs?

Emailed the salesman, but their demo has long gone and haven't got a replacement S yet.

[GaryF]

Might be worth checking the oil level just to be on the safe side to ensure it is not low (unlikely, but just for peace of mind).