urojohn

2011 S4, 96 K miles, supercharger making a whining like noise from the bearing, much like a power steering pump that is failing. No noticeable change in performance, etc. Does anyone have any experience with this type of problem or any idea what may happen. It has been doing this for about 4k miles. Thanks

vector78

Loud whine that goes away when you pull the dipstick or oil cap is indicative of the PCV valve going bad. It is located under the supercharger that its diaphragm is known to fail.

urojohn

Thanks for the tip, I pulled the oil filler cap off and same noise; also, I actually had the PCV valve replaced earlier this year for an oil consumption problem (it fixed that). I'm just going to keep driving with it whining since there seems to be no loss in performance and see what happens, it has been making this noise for at least 8 months and it seems unchanged.

VONBOTTLE

curious how it's driving? my wife's S4 is has been making the bearing whine for a couple months now - trying to gauge how long i've got before i have to replace the charger, really don't want to sport for a new one so i'm trying to find a decent used one, unless anyone knows of someone who sells rebuilt ones?

urojohn

No noticeable performance change, still making the same noise, no worse, don't plan on doing anything unless it stops working, now have 103K miles.

VONBOTTLE

gotcha......i imagine the noise won't get much worse and as yours, performance seems to be about normal, but just wonder when/if something catastrophic can happen? i have sourced a charger with only 2k miles on it from a 2011 A6 which a guy has had sitting around in his shop and can get it for a pretty reasonable price, so i will probably jump on it and then replace it when i have some cash burning a hole in my pocket. it's the next revision part # (K), mine is a G, so whatever that's worth, not sure what improvements have been made in the last 6 or 7 revisions