Hi Got a A3 2.0 tdi 07 plate. Engine keeps going in to idle mode when I reach a certain amount of revs, a warning light on dash and a whistle from the engine, is the turbo shot? cracked pipe? faulty seals?....Help!! Had engine cleaned, by this I mean I paid £120 to a garage to spray an aerosol cleaner down an air intake pipe, didn't work..