Mystery sound in my D4

[Watpub]

Hi guys,

I need some advice about a noise that seems to be coming from the engine or transmission in my D4 HSE.

It's a very slight whining-type of noise as I accelerate generally from the lower speeds. It's a hard noise to describe - it's intermittent, not particularly loud, and lasts only a few seconds. I can't really give it a decriptive sound - it's not a whine, and it's not a vibration, and it's not a grinding sound: it's sort of a little of all of these. And I can actually "feel" it too as a slight vibration/rumbling through the steering wheel.

I may be wrong here but it seemed to begin after I hit a substantial pot hole going home from work in the dark last week :mad:. Must be an election year in Victoria because every road around the place seems to be dug up at the moment.

It also seems to be getting more regular.

I'm not mechanically minded in the least but I was wondering if it could be one of the turbos? Any ideas or suggestions? Should I be worried or just leave it till the D4 needs a service?

Regards Ron

PS: I can't hear it when the radio is turned up :p. I can still feel it in the wheel though.

[AnD3rew]

Could be quite a few things from several sources, but since you mention the pothole, it could be wheel alignment or balance, onle real way to check this is to get it checked out at a dealer or tyre place, would be easier/cheaper to check balance first and failing that alignement.

Also worth giving the tyre which copped the pothole a good visual inspection and run your hands over it, missing chunks, bubbles deformities etc could all cause those type of symptoms and you may misinterpret it as engine/transmission especially since you say you can feel it through the steering.

If you are not used to a turbo vehicle, you may just be noticing a normal turbo sound, however I must say I dont notice it from inside the car on my D3, but then I only have 1:mad:

[Neil P]

Can we assume your suspect wheel has its balance-weights intact ?

[WhiteD3]

Air con compressor? Turn off the AC and radio (in case its "noise") and see if you can hear it. I suggest this as I had a "whine" in the car after 2 years which turned out to be the AC.

[Watpub]

Thanks guys,

AnD3rew,
I've had a cursory glance and feel of the wheel and tyre and haven't come up with anything out of the norm. So visually it seems to be okay, but I haven't got under and around it yet.

Neil P,
I'll check the balance weights out tonight after work.

My only concern here is that if it was a wheel problem you'd expect it to be more consistent and not so intermittent - also, it's not a wobble, but rather just a whining-type of noise.

WhiteD3,
Tested your theory this morning. I switched off ALL of the climate contol features (a/con, heating, fans, etc) and the radio - I almost froze my whatsits off (lucky I had the heated seats and wheel and my new seat covers :p). Actually there was a significant reduction in the noise. The problem was it was so quiet I started to see dead people - well not really, but I began to jump at every noise I did hear and I thought I caught odd smatterings of THE noise that's causing concern. I'll test this theory out over the next few days with on and off air con scenarios.


Thanks all for suggestions. They're all super-appreciated. At least nobody's suggested "rush back to service NOW".

Ron

[Neil P]

So it's NOT a vibration through the steering wheel now ??

[Watpub]

So it's NOT a vibration through the steering wheel now ??

You can certainly "feel" it through the steering wheel when it goes off, but it's not a wobble or a shake as you'd get with an out-of-balance wheel. For want of yet another word maybe "buzzing" through the wheel is more appropriate.

It's a really subtle kind of "annoyance", neither definitely one thing or the other - that's why its driving me nuts!

The wheel angle of yours is interesting. You know when you run over those raised marker strips on the side of some major highways (like the Hume) which are designed to startle you in case you're getting drowsy and drift across the road? Well, it's a much quieter and subtler form of this. But the problem is it's intermittent.

As I mentioned in my post it seems to have diminished today after switching the air con off so it may just be an intermittent vibration from here. But maybe its just gone on holidays for a day or two. I've got to try a cuppla days with/without air con to see if this is the problem.

Thanks for your suggestions.

[Neil P]

.......... neither definitely one thing or the other - that's why its driving me nuts!

Thanks for your wild guesses.

Mine has a vibration at "just before gear-down" , on a upward climb.
Are you sure it's not just the vehicle being a moving 2600kg , permanent
4x4 .

Options :

1. Increase medication
2. "Get real" and live with it
3. Remove seat covers
4. Burn it out for the insurance and buy a demo Porsche Cayenne Di ( you know it makes sense ! )

[Watpub]

Mine has a vibration at "just before gear-down" , on a upward climb.
Are you sure it's not just the vehicle being a moving 2600kg , permanent
4x4 .

Options :

1. Increase medication
2. "Get real" and live with it
3. Remove seat covers
4. Burn it out for the insurance and buy a demo Porsche Cayenne Di ( you know it makes sense ! )

Thanks Neil P...

Option 1: Probable - although the doses are already high
Option 2: Realistic
Option 3: Never!
Option 4: Porsche Cayenne? Que? I'd upgrade to a Rangie and really stick my neck out.

On the insurance side I've had one car totalled (taken for a joy ride and written off), and another t-boned on the side of the street when I was in the office. Even though I was no-where near the cars at any stage I've still had to suffer the ignominy of making claims - after that no other insurer wants to know you for at least 3 - 5 years! You mightn't be "at fault" but you still suffer the discrimination. I'm steering well clear of insurers...

But, I think you are right. It's a big hunk of metal with many intricacies. I just put the issue out there (here on the forum) in case there was something I should be worried about or someone had a quick fix. I'll turn up the radio and wear gloves - that'll fix it!

Regards, Ron

[Neil P]

Well , that's resolved ! My Bill is in the post :beer:

[CaverD3]

Idler pully bearing shot? Common occurence.

[Watpub]

Idler pully bearing shot? Common occurence.

It's only a few weeks old? I'll raise it when serviced or earlier if it persists. Thanks Ron.

[brad72]

Just a long shot but the main hydrostatic engine cooling fan comes on intermittently in my D4 and has that low down hum that you can hear driving along. I only hear it under 60kph. Could it be this

[RoverLander]

Hi whatpub,

In one way i am happy to read your post. I have the same difficulty describing the change in sound and feel that my D4 developed during a recent long trip. I describe it as:

Inconsistant
Slightly worse when cold
Happens under moderate acceleration at slow speed
Slightly worse when driving up a steep hill
Creates a turbo like sound but slightly sicker sounding
Creates a vibration that at one time i could feel in the car
Doesnt seem to effect anything else. Power good. No smoke. No oil consumption.

I reported it at my service this week. Very good dealer service. Lead mechanic came for a drive and heard the sound. They investigated but could not isolate it. They took note on my service record and asked me to monitor and come back if it gets worse.

Its not bad enough to say its a significant problem. It is just that it wasn't there before and it is causing me concern.

My car is a 2010 D4 TDV3.0 with 37Ks.

Has your noice got better or worse? Any answers or solutions?

[kenl]

Well I think I have the same sound/vibration, and had put it down to tyres. I asked the dealers and they just fobbed it off.

My sound is a bit like going over rough edge markers that we get on the major roads, but not as severe.

You can both feel and hear it.
It only occurs around the 50 to 60kmh range
Seems to not be there when the roads are wet?
More likely to be there when coasting or slightly decelerating
Is still there if car is put in neutral.

I rarely notice now, but did the other day when SWMBO asked about it, so I'm not sure if it's there as often now? I don't think so? (now at 15k) My 2010 D4 had the same tyres and engine but I never noticed the sound or vibration. I had however moved from a 2001 Td5 D2 so it was very, very, very quiet in comparison.

[Watpub]

Hi RoverLander,

I reported it at my first service and it was suggested that it was just normal "resonance" (whatever that may mean in a vehicle!). It was even quipped that I turn the radio up if it annoyed me too much!

To be honest I've either adjusted to it or it's gone away. I certainly don't notice it any more.

I did ensure though that it was documented at the service just in case it flares up into something serious in the future.

However, now that my touch-screen (and therefore radio, GPS, bluetooth, cameras, etc) have died - see recent post - I may notice it again!

Ron

[TerryO]

Mine makes what sounds like a similar hard to notice noise at slow speeds when you excellerate away slowely or with a on again off again trailing throttle. Go for a drive with the drivers window down and I bet you can hear it quite loudly compared with the window up. That is if it is the same noise and yes you can feel it very slightly through the steering wheel when the noise happens. Well you can on my D3 anyway.

Mind you my airconditioning compressor just failed so once it is fixed it will be interesting to see if it the nosie and the vibration goes away.

The thing is most everyone always drives with music on and you can't hear it with the radio on, so maybe it is quite common and nothing to be worried about.

cheers,
Terry

[Graeme]

since you mention the pothole, it could be wheel alignment
Is the steering wheel still straight? A slight whirring sound could easily be caused by the alignment slightly out. Although not a conclusive indicator, I'd expect the steering wheel to slightly off centre though.

The slight cupping on the outside edges of my front tyres causes minor noise and vibration through the steering wheel at slowish speeds on some surfaces so its time the tyres got shuffled.

[RoverLander]

I've done a bit more testing on this....and I think it is engine or transmission related. It happens around 50 to 60Kms per hour and when going from coasting to moderate acceleration.

Aircon on or off makes no difference.
I have put it in manual at that speed and there is no noise. I dont believe it is a tyre noise.

I will get a wheel balance and allignment in the next few weeks when I get a TPMS installed and see if that makes any difference but I suspect it wont. I'll post any updates here.

Peter

[Graeme]

I have put it in manual at that speed and there is no noise.
Unusual noise from torque converter whilst not locked? All your previous clues could indicate either a normal or an abnormal torque converter noise.