I have 2010 range rover supercharged. I used to hear the supercharger whine under load or fast acceleration (which I liked a lot). After I had the supercharger serviced with new nose cone and coupler, I can hardly hear the supercharger any more, even under heavy acceleration. The power still feels the same as before the supercharger service.
Is this normal or should you always hear the supercharger under load ?
They also replaced a faulty PCV valve, perhaps the faulty one caused the whining sound to be louder ?