Help me figure out this terrible engine whine - C55
02-20-2010, 11:51 AM
#26
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2008 A8L, 2002 996TT X50, 2009 X5
sounds like one of the idler bearings have gone bad.
this is how mine sounded when the supercharger bearing went bad. http://www.youtube.com/watch?v=LAcmJRZrpBo
I also had one of the idler bearing went bad and blew apart. no sound clip tho, but pretty much the same noise. it comes and goes because when you stop and let off the belt tension decrease and engine noise dies down which makes the grind more apparent.
this is how mine sounded when the supercharger bearing went bad. http://www.youtube.com/watch?v=LAcmJRZrpBo
I also had one of the idler bearing went bad and blew apart. no sound clip tho, but pretty much the same noise. it comes and goes because when you stop and let off the belt tension decrease and engine noise dies down which makes the grind more apparent.
Viper - sorry for the OT, good luck with your situation.
02-24-2010, 08:27 PM
#27
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Any tips on releasing the tensioner? Are you just supposed to rotate it counterclockwise via the center bolt? The center bolt seems to be a tamperproof torx, T50? Any confirmation?
02-24-2010, 08:32 PM
#28
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white and whiter
OT for this thread, but Frank, if you're referring to how the S/C pulley bearing grind/rattle noises come and go, by my understanding it's because that bearing is only working when not under load. So as soon as the S/C engages, the noise goes away b/c the bearing isn't spinning. Mine's pretty bad right now - need to get to the dealership svc. dept. for a replacement.
Viper - sorry for the OT, good luck with your situation.
Viper - sorry for the OT, good luck with your situation.
the vid of s/c bearing noise is just showing how might a bad bearing sounds like. they all sound one way or another the same.
02-27-2010, 04:06 PM
#29
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In case anyone was curious, the new pulley bearing is tight and doesn't make a peep.
http://s372.photobucket.com/albums/o...dlerPulley.flv
http://s372.photobucket.com/albums/o...dlerPulley.flv
