V50 D intermittent whine at tick over

[7050man]

I've recently purchased a four month old V50 2.0D. Pleased overall with the car, but a couple of weeks ago I noticed a distinct medium pitched whine, only at tickover after the car had been driven for a couple of miles.

When apparent, the noise goes immediately the throttle is touched but will come back as soon as the revs drop to idle. Noise also goes when the steering is turned. Depressing the clutch makes no difference.

Had a listen under the bonnet, but not obvious where it is coming from.

Has anyone experienced this before or have any clues?

Car is a MY 2006 E4 engine.

thanks Jez

[Marmoset]

Sounds like it could be a bearing in the alternator or any other thing connected via the seprentine belt (tensioners etc)

Does it go away when the air-con is turned on/off?

[7050man]

Sounds like it could be a bearing in the alternator or any other thing connected via the seprentine belt (tensioners etc)

Does it go away when the air-con is turned on/off?

I can't be sure now, but I think I tried that and it made no difference.
My initial thought was that it was an elecrical whine as opposed to a mechanical grinding sound. A very consistant tone with no fluctuation of the pitch. A bit like running your finger around the rim of a wine glass and making that ringing sound.
The only variation was in the volume. When I first noticed it, it was a fairly obvious sound, but even when the level had dropped at another time, I still thought I could feintly detect it.

I have read a thread somewhere on here about the alternator bearings, so that was my first thought as well though.

I'll keep you posted. Jez

[Marmoset]

As the power steering is electro-hydrualic then it will exert a load on the alternator when you steer - it could well be alternator bearings then

[IRES40]

hi there i have a 2006 volvo s40 2.0d se
it has the exact same problem , i have 1400km on the car and its 3weeks old
i just posted on here about it..

i had a look under the bonnet and it seems like its coming from the area around the fan belts... i havent a clue about engines...but its the very same problem!! when i touch the accelerator it goes away..

when the car is started from cold there is no sound. sound only appears when car is warm..


have you had any joy in finding out what the problem is??
i am taking my car over to the dealer tomorrow morning to have it looked at.

[IRES40]

hi i just had a close look at my car,... drove the car no sound at all until car reached normal operating temperature then when at normal engine temp sound was there on idle. rev the engine a little and sound goes away, until u let the engine idle again..

i think the noise is coming from the alternator, denzo 150A was written on it.
when i turn on the aircon and also the back window heater and radio ( ie put a load on power) the sound seems to get lesser...

150A seems quite a lot for an alternator for a car!
if its the bearings as some people suggest how come it goes away when you increase throttle a little...

?
any ideas? what it could be?