HELP NEEDED!!! boosting problem

[Tasha Gower]

I have not long owned my cupra R for very long and already had the water pump etc done last week.
But last night i noticed my car was not responding properly it felt like a 1.4. I can hear the turbo whistle when drive but it is not boosting like it did.
Had a look over 2day and all the pipes seem fine none have come off that i can see.
So ur help wud be greatful on what u think it maybe. What are the chances of it being a broken turbo!!!

thanks tash

[Tasha Gower]

forgot to say its an

'1.8 20v T Ibiza Cupra R 51plate'

[cuprakyle]

maybe try changing the n75? may be a leaky valve . .

[fossie]

Sounds like there may be a leak in the boost system somewhere