Ever since I picked up my '05 911 C2 (about 3 months ago) I've slowly noticed a mid/high range whining tone at idle, and frequency increases with the engine speed at low RPMs... Not sure if this is the fuel pump or perhaps this is just normal operating sound. It's not terribly loud so I assumed it was normal, but thought I'd ask... It's CPO so I'll get it looked at if necessary, but appreciate any input!

 

Did you ever resolve the source of the whining sound? My 2011 C4 has something similar and I don't know whether to be worried or not.

 

No one can answer this w/o hearing your motor but:
If you are referring to the lovely whir of gears, pulleys and chains and other moving oily things that accompanies the running Porsche flat 6 I would suggest you relax and learn to love it. Having said that if you think you are hearing something that shouldn't be there I would pay a visit to my nearest dealer and listen to another one. My money is on relax and enjoy. If you ever get the chance listen to an idling aircooled. Porsche worked hard trying to reproduce that sound.

 

My 2010 997 has a constant whine/droning which is most noticable at idle. My indy noticed it as well but couldn't trace it to its source.

Car runs fine otherwise so I'm trying to ignore it.

Regards,

CF

 

I only hear whining in my car when my wife is with me.

 

+1k !

 

Hahaha .... that's superb! My wife grabs the dashboard with both hands before it's even down the driveway!

 

the "hum" is normal. My car does it and I hear a lot of people have it too.

 

Could be bearings in one or more of the drive belt idler pulleys are shot. Not uncommon on older cars. SunCoast sells the whole set of 3 together. Way to check, disengage the drive belt and spin individual pulleys by hand. Good pulley will spin freely with no noise. (If you remove the belt mark it's direction of rotation so that when you replace it it will rotate in the same direction as it was installed or, just replace it with a new one for $30 and don't worry about direction of rotation.) The rational for replacing all three pulleys at once is the assumption that if one is shot the other two are probably not be far behind.