Citroen Xsara Picasso 2.0HDI (attempt 2) strange whirring

[Lawrence1973]

Now, I see quite a few people read my post......no replies though

I will go into a bit more detail to try to tease a response out of someone!

I have just bought the car and I'm new to the HDI engine. I picked the car up, started it from cold and I could hear a quite loud whirring sound from inside the car. It winds up and down with engine revs but you can't really hear anything from outside with the bonnet up.

To tell the truth it sounds like it's behind the dash board. As the car warms up it disappears but will be back again when the car is cold.

I am concerned that something is worn and as it is under warranty, I want to point the garage in the right direction with an experts view.

I have read about timing belts, alternator bearings, power steering pumps, coolant pumps. I'm not convinced about any of these as I would assume the sound would be the other way round - getting worse when hot.

Anyone help please?

[VertVega]

...
winds up and down with engine revs but you can't really hear anything from outside with the bonnet up.
...

My guess is the heater blower motor which is under dashboard, behind trim on the passenger side (in a Xantia ).

[Lawrence1973]

Cheers but it seems independent of all that.

if the heater blower is turned off, the sound remains......?

It reminds me off a worn pump kind of sound - but it seems so close to the dash

[VertVega]

There's an electric motor with a mini propeller for the interior temperature sensor.
This is a very small motor could it make such a loud noise?
Try listening close to the area which is marked as number 5 in the picture.

[Lawrence1973]

Cheers,
I'll have a go in the morning.

Would this go up and down with engine revs?

[VertVega]

"go up and down with engine revs" makes me think that its electric motor related and there is rotational movement .
(flaps are also controlled by an electric motor but they do not rotate continuously.)

[Sl4yer]

Is some part of the exhaust (or something else connected to the engine) connecting with the underneath when it's not supposed to? Could disappear when everything is warm.

James

[RichardW]

Noises on HDi's present engine cold that go away when it warms up are often due to the crank pulley breaking up - check to see if it's rusty on its face, or worse there's evidence of metal shards coming off it.

[Lawrence1973]

Thanks all,

Will check, Richard, is this due to over tightened belts? worn timing belt?

Cheers

[CitroJim]

Yes indeed, a mis-tensioned cambelt can give rise to noises like this, especially where they rely on a manually adjusted tensioner as the earlier HDis do.

It'll be well worth replacing the cambelt as a precaution anyway (along with the waterpump!) and ideally using a SEEM gauge to set the tension correctly.

A good rule of thumb though is that if the belt can be twisted 90 degrees on it's longest run between finger and thumb, the tension is abut correct. Remember to set the tension a little loose on a clod engineas it expands and tightens the belt a little when hot.

[Lawrence1973]

Cheers Jim,

Is this a common thing? I am confused because it really does sound like it's right behind the dash. but I know from a bit of experience that it can be misleading.

At working temp, the sound has completely gone. Would this fit the bill?

I am out of my depth with this engine so I don't want to tackle something too painful! Chances are it's not covered by the warranty though!

Cheers

[makok]

Hi Lawrence, everybody,

although it's been a few years, now I have exactly the same problem, same car, same engine.
But there is no solution.
How did you work it out? You remember back to that?

Thank you.

[wheeler]

Removing the alternator drive belt & starting the engine can quickly rule out the noise from PAS pump, alternator, A/C compressor & the accosiated tensioners/rollers.

[Kennyd90]

It sounds like your turbo. It could be a loose hose on it or from it. It's behind the engine up against the bulkhead. If there are no loose hoses and your not loosing any performance or any sign of turbo wear, I'd just live with it.

[GiveMeABreak]

Removing the alternator drive belt & starting the engine can quickly rule out the noise from PAS pump, alternator, A/C compressor & the accosiated tensioners/rollers.

I agree with KennyD - sounds more like a turbo whine as you won't hear it until it spins up with the revs. If it is a hose leak, it only takes a very small one to make a big difference - and these are not very easy to find - took my garage 2 attempts to locate a small split not visible to the eye before they replaced the hose. My car had no power and was spluttering like anything until they found the leak - it was almost undriveable, but depends of course if this is a leak and where it is - or whether it is the turbo itself.