Hi all
I have an 09 q7, 4.2 TDI twin turbo.
Under medium to hard throttle the car makes a chirping/whistling sound which sounds like it is coming from the drivers side ipof the vehicle.

I have checked the car for boost leaks and have in fact replaced both intercoolers(the sound was there prior to intercooler replacement).

It's driving me nuts trying to figure out what the hell it is.
To give a little more insight the right hand intercooler had been previously damaged and given a dodgy repair, when I drove the vehicle for the first time I felt something let go (intercooler repair failing). Ever since it has made this dam sound.

Does not make the sound when vehicle is stationary and revved hard, only when in motion and into the throttle.

Any suggestions would be really appreciated

Rgds
Darren

 

Awesome response, glad I posted