Lack of power (acceleration) for first few minutes when driving

I recent bought this car and the problem I have is there is no or very little power (acceleration) in it until the engine heats up to normal driving temperature and it becomes normal again. There is also a loud whistling noise when I give her throttle which makes me believe it has something to do with the turbo. It also might help to tell you that the car was lying up for a month before I purchased it which may have led to the problem. If you have any idea what this problem is it would be appreciated.