Have noticed when I'm taking the kids to school with the windows open, there is a very audible hissing sound when accelerating. I'm unsure if this is what the turbo is meant to sound like or if I'm suffering from a cracked hose somewhere.

Hopefully you can hear it - as I start going up the hill.

 FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…

It does sound like the beginning of a turbo leak to me. Check all your hoses and connections carefully. You may see some oil 'misting' where pressure is escaping. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.

Cheers. Will take a look, not that I know what any of the pipes in there are! FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…

That sounds more like a crack in the manifold. Seen it before and it is only solved with a new turbo. Freelander 2 HSE Lux 2013MY - Barolo Black with Ivory Leather. Alpine DVD - Privacy -Evoque 20" Dynamic Wheels and more to come.........

Not what I wanted to hear (literally)! Any way I can check this at home before taking it to get checked/fixed? Really can't afford to be chasing faults just now.

Thanks. FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…

There is more easy fix that was reported here several times, check the rubber seal of the steering wheel shaft, if it is sliding out noise is coming in to the cabin.
The hiss sounds normal but louder which can explain a "leak" between the cabin and engine compartment

I should clarify this can't be heard unless the windows are open, so unlikely to be the steering column seal. But thanks for the suggestion. FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…

does sound like a leak or a split in something.

I would check the exhaust as well.

Iain

Sounds like I'm going to have to get this checked by someone. I don't know where and what to look for by the sounds of things.

If left would either a cracked turbo or exhaust cause any damage? FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…

won't cause any damage, but usually only gets worse.

if you're near strathearn engineering I would pop in and let them have a look.

Iain

ps sorry for some reason I thought you were in Stirling area.

I was Iain, but have since moved. Might get Mikey from MMP a shout next time he is in Edinburgh. FL2 TD4 GS 60 reg Facelift - so many issues
2019 DS. Terribly unreliable.
Sold DS for a 2021 Mitsubishi Outlander PHEV. Fingers crossed....
Sold Outlander for a 2014 SD4 SE Tech because I’m mental
Now greatly regret selling the Outlander. MPG of the FL2 is atrocious and so are the fuel bills. Fun though 😎
Couldn’t afford the fuel bills so back to an older Mitsubishi Outlander PHEV. Significantly better than I remembered it to be…