Hi, am trying to track down a funny whistle sound comming from my engine bay, also revs under idle drop at times, have had AFM rebuilt ect, I\'m leaning towards th BOV leaking.
Now I\'ve removed the BOV and it might sound like a dopey question but are you meant to be able to blow a bit of air through the inlet to it when its off the car or are they meant to be 100% airtight, I\'d imagine if I can do this that the seal is getting worn and I could imagine a couple psi leaking past it under load as the whistle sound only comes in under light boost.
1997 gtb legacy
Any help would be great