A slight whine/humming noise

[blacklab]

Just noticed today my V50 2005 2.0D is making this whine/humming noise from the engine, that's how I can only describe it, sorry.

It only happens when revs are applied as on tick over it's not there. You can here it whilst driving, it's not an unbearable noise.

Had a listen with the bonnet up and its not coming from the alternator, it's just a strange noise!

Just wondered if you guys have ever had this?

Any ideas? Thanks.

[DavieC]

Mine was making exactly this noise until two days ago, when the alternator blew up (well, judging by the smoke and the burning smell it must have done).

[benr7310]

hi blacklab,

would you be able to record a video of the sound your describing and either youtube it or photobucket it and share the link?
might help diagnosis :)

[blacklab]

DavieC, how long did you have the noise for out of interest? Can't hear a noise coming from the alternator when the bonnet's up.
You know when you hear older diesel cars turbo whistle, well it's not exactly like that, but if you can imagine a quieter version of this noise.

Car goes a treat otherwise.

benr, hadn't thought about doing that?! Ta

[DavieC]

I couldn't place the noise for a while, but I could hear it getting louder with engine revs. I had someone lightly apply the throttle whilst the bonnet was open and it was clearly coming from the alternator. Stupidly I thought I'll sort it after christmas unil I was 15 miles from home and I got the power system service urgent and batter warning lights on the dash.

The noise is similar to the turbo noise, however on my car this can only really be heard with the engine loaded and moving, the alternator whining however could be heard with the car idling and was a good bit louder.

I got the car back today, £300 for a new alternator fitted, so fairly happy.

[blacklab]

Thanks for the speedy reply.

Interesting bit is there is no noise when on tick over but can be heard when engine is under load or revs applied when stopped.

Did you go for the 150a alternator as mine has this but it's a 2005 so I guess it got replaced before I had it. I gather they used to be 120a? No doubt someone will advise on this.

[DavieC]

Mines a 2006 S40 2.0D. It had a 150a alternator.

[Guru]

Interesting bit is there is no noise when on tick over but can be heard when engine is under load or revs applied when stopped.

High pressure fuel pump? just a thought...

[blacklab]

Now that's just expensive! Lol

I guess I'll just keep using it and see what happens I reckon?!
Will keep you posted................

[blacklab]

Update..Called in to the indi today who says that the noise, like davieC said, is from the alternator. So I'm going to take my chances and see how long it lasts!

[Shedburner]

Got the same noise coming from my V50 2.0D. my friend took the alternator belt and the noise went away, so not the turbo thank god. But we could wobble the pulley on the air con compressor so thought it could possibly be the bearing gone in this.
I haven't done anything about it as of yet. Was just hoping to get some feedback on here, wouldn't want to spend £300 on a a/c compressor only to find out its the alternator.
But looks like from all the posts.........could be the alternator. :thumbs_up:

[blacklab]

Lol, just replied to your post!

[DavieC]

Just an update, I was cleaning the car and had a look under the bonnet at the new alternator. I was thinking I'd maybe see a volvo or ford logo somewhere, but no it's only a genuine GM one.

[138gat]

Mine sounded just the same last year, (04 2.0D S40) only lasted a couple of days before i got the "power system service urgent" warning and the alternator packed up. £185 inc vat from local auto electrician for a exact match 150 amp

[alexstanley]

Had the exact same issues - whining noise from the engine bay. Suspected the alternator but thought i will get it looked at in a day or two (got to get work etc etc!).
Bad idea! If you have a whining noise and smell metal overheating get it changed pronto! You do not want to be limping home from work at midnight with heavy fog and rain when it finally packs up - I lost the lot: fog lights, full beam, power steering, abs, srs and almost head lamps, the dash looked like Blackpool Illuminations - not fun!
I managed to pick up a new alternator for £160. It was a 120amp for my V50 1.8. Took two hours to change myself and was a bit tricky - took a while to get the connecting cables off the old unit.

[Bendolfc]

Replacing it with another 120 is probably false economey, ideally you should fit a 150A and have volvo update the software so it knows about the larger one.

As to the earlier question, I beleive originally they used the 120A on cars without heated seats and 150A on cars with them, at some point they changed to 150A regardless due to the failure rate. That said, the 150A ones fail too, although in my case probably down to the missus love of the heated seat.

[blacklab]

Alex - How did you know how much tension to put on the belt when re fitting it? Bit of a guess type thing??!

[blacklab]

Update....

Went down the road from home 500yds and guess what the dash lit up and the battery light came on along with the message!
Will get it booked in on Monday to have the alt changed.

So to sum up, if you hear it make the noise you don't have many days before it packs up!