Update.............



Found one of the vacuum pipes on one of the boost valves on the n/s inner wing split, replaced that and thought had cured it

Now the eng management light comes on at idle after about 5 seconds and goes back to having no power again, checked the oil level and was on the minimum so topped that up and was hoping that would have cured it as someone said low oil level could cause this fault but unfortunately its still the same

The light comes on at idle and will go out eventually after you drive off but varies on the amount of time it takes to go out, can go out and you are back to full power after about 5 seconds and other times it can take about a minute before it goes out, always comes back on again after letting the car idle though and when its like this it wont rev above about 3.5k.

Any ideas ????????