I was getting the moaning/whining noise from the supercharger area on deceleration, and upon checking the forums saw that a squishy PCV hose might be the cause of the problem. Sure enough, my PCV hose was oil-soaked, and I had it replaced at the dealer.

However, 1 day later, it is 94 degrees (F) outside, I have the aircon on and once again I get the moaning on deceleration. It is not as dramatic nor as incessant as it once was, but it is definitely still there. The breather hose seems securely attached, and is definitely much firmer than the old one. I checked my PCV valve-- it rattled, which (according to the forums) means it's OK too.

In motoring about, I notice that the noise seems to show up more often after "spirited" driving

So, any ideas on why I still get the moaning noise on deceleration?

Any help would be appreciated.

 

Moaning after spirited driving.....sure it isn't the "afterglow"? Sorry, couldn't resist...someone on here will have some better suggestions for you.

 

The a/c will create a droning noise in hot weather occasionally. If you hear it again while driving, switch off the a/c. If you no longer hear it, it was the 'normal' sound of the a/c compressor.

 

Thanks, I'll give this a try once it gets hot again. As long as it's "normal" I won't worry about it.

 

Yeah...what GreatBear said. That's probably it.