Noise when slowing down -diesel van

[Boz]

Just joined the site , but have found it helpful for a few years now. I have a 2008 1.8 diesel van and when slowing down there is a noise that seems to come from behind of what sounds like a motor slowing down. It’s still audible when idling. Doesn’t happen all the time and no obvious pattern or trigger. Any ideas please?

[brodfather11]

could it be your exhaust loose and only touch the body somewhere when slowing down.

[Boz]

could it be your exhaust loose and only touch the body somewhere when slowing down.

Thanks. It's not a noise I've heard on a vehicle before, that's the odd thing. It continues when stationary, and definitely sounds like a whining noise of a motor slowing down.  I've also got a juddering on acceleration, and flat spots on power on changing gear. Someone suggested it might be the turbo going - could the 2 issues be linked?  I've not had a turbo go before so don't know the usual signs.

[Sol]

Hi, sorry to be picky but there is no 1.8, so the 1.6 has a turbo and the 1.9 doesn't, so which actual engine model do you have?

And if the noise comes from the back, it can't be the turbo as that's mounted to the front of the engine.

It does this noise when sitting still, engine running, in neutral (not in gear)?

[Boz]

Hi, thanks. You’re not being picky at all- I appreciate your help. It’s a 1.9 diesel, sorry! So definitely no turbo , ha ha! We’ve had it 8 years and love it; it’s been a great van and given us lots of happy memories.
I’m not sure if it does it if in neutral, whilst still and running, so I’ll check and post an update. Cheers

[Sol]

No worries. So if it only makes a whine when moving or slowing down, even out of gear, it is more likely to be a wheel bearing heading south.

Not sure if the 1.9 has an electric lift pump in or near the tank, that would be another possibility for a noise but would be there all the time and not speed dependent. I've had both models in the past but never had to do much repairs in that area so not sure. Someone who has an M59 now will know if it does. (@saskak, @jj9 and others)

[saskak]

On my 1.6HDi 2007 M59, I have heard similar noise at the rear, but never understood what it is. There is not much of a pattern, but I think it is mainly on a harder bump or say coming from a curb and generally related to the beginning of a drive from cold. My sound lasts a sec or so and happens once per journey from cold. It is not a whine, but it is difficult to describe. It is like an electric motor driving some adjustment screw type thing.
I thought to investigate, but I always forget about it.

[Gryffindor]

I know it's nowhere near the rear, but just to rule it out, it isn't the radiator fan by any chance?