[klipseracer]

Originally Posted by psu139

I read over in another thread that someone had thier police siren sound fixed by tightening pulleys/pulley replacement. Does anyone know more about this such as SIB? Here is the original thread

http://www.e90post.com/forums/showthread.php?t=310642

Alternator whine? Sorry I didn't read the thread just putting it out there. Do you have a system installed with an amp? Hope that helps you. There is another thing that our cars do that gives the ambulance whine. I'll have to find the thread for you. Means your turbos are going out.