Aston Martin DB9 - 2007

Hi from Sweden!
I’ve got a DB9 from 2007. When the engine has reached normal temp there is a swirling/wheezing sound, following the rpm. First I thought it was the tensioner assy for the engine belt drive, so I changed the whole kit with idlers and belt. The sound is still there and sometimes a second sound accurse, a small squeezing like a hydraulic pump that almost runs empty. The air-condition seams OK, the oil cooling system is checked. Only thing that seems strange is that the cooling fan is running almost constantly. Please, let me know if you got any bright idea about what it is... Best regards from proud Aston Martin owner in Sweden!