Whistle driver side engine 2500rpm

[nickgla]

Hey guys my 2005 xc90 has started a whistling/whine when the revs hit 2500rpm. Under 2500rpm no noise at all.

Just looking for any advice where to start looking to fix. Noise seems to be drivers side.

I have took a video if I can figure how to upload I’ll do that also.


Edit: only happens when driving on idle when I there is no noise. So only on acceleration when it hits 2500

[SnineT]

From idle stationary rev it to 3000 rpm then listen as the revs drop, if it's like a siren winding down your turbo is unbalanced and scraping the housing wall.

Get that one out of the way first.

[nickgla]

Link to the video I took of the noise. https://files.fm/u/xjcxewf78

Only happening under acceleration, spent all afternoon and can’t figure it out.

[SnineT]

I can't think what that might be other than something is loose and at the right time it resonates like a bell.

Glad to say it's not your turbo though.

Does it sound engine compartment or in the dash?

[nickgla]

Sound’s definitely coming from engine compartment driver side I’m sure. In park and revving the engine there is no noise.

[ca2n]

From the video I can see the sound appears when you hit around 2500 rpm and 40 mph. Does the sound appear when you're going at other road speeds at 2500 rpm?

[SnineT]

Originally Posted by nickgla

Sound’s definitely coming from engine compartment driver side I’m sure. In park and revving the engine there is no noise.

If you saw this reply I've edited it and you should ignore it and follow whats below.

I had another listen and it really does sound like metal resonance somewhere, what you need is to take the bonnet off and get someone small to listen while you drive, make sure they strap onto something though

Seriously though it's going to be a nightmare to locate it due to it having to be driven to make it happen, maybe if you have an old mobile phone that you can secure under the bonnet and shoot a video of it while driving it might give you a better location, you might need to do it above and below to nail it down,or better still if you have a long lead mini mic that could capture the sound for you.

To make what I said a bit easier to understand imagine a bike bell being ting'd and I think this is what is happening somewhere, something is lifting just enough to contact something (could even be it's own mounting) causing a resonance.

[Lancee]

Take it to a rolling road ?

[TruckbusUK]

or 4 axle stands alt a suitable lift if you can find someone to let you use it .... some garages/workshops rent space, tools and lifts at the weekend.

Worth finding out about.

[SnineT]

Originally Posted by TruckbusUK

or 4 axle stands alt a suitable lift if you can find someone to let you use it .... some garages/workshops rent space, tools and lifts at the weekend.

Worth finding out about.

I don't think that will work as it probably needs the engine to be loaded, the rolling road might show it. My own thoughts are that it's in the exhaust somewhere maybe a heat shield resonating or a baffle going bad, there's so many things it could be but it needs the silly things checking before going in deep, I've seen things like this just be a tool left loose in the boot or a door bucket, kids toy rolled under the seat and because it only does it in one specific parameter it would suggest it's something loose doing it rather than a failing part.